Data Source & Methodology
AuthoritativeDataSource: Consumer Financial Protection Bureau (CFPB) — Payday loans guidance & research (ongoing), and the standard APR conversion from a periodic finance charge: CFPB: Payday loans.
Tutti i calcoli si basano rigorosamente sulle formule e sui dati forniti da questa fonte.
The Formula Explained
Let:
- \(P\) = principal (loan amount)
- \(f\) = fee per \$100 (e.g., \$15 => \(f=15\))
- \(d\) = term in days for one period
- \(n\) = number of rollovers
- \(A\) = one-time admin fee (optional)
Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\)
Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\)
Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\)
Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).
Glossary of Inputs & Outputs
- Loan amount: Original principal borrowed.
- Fee per $100: Lender’s periodic charge per \$100 of principal for the term.
- Term (days): Days until the loan is due.
- Rollovers: Count of term extensions that add another fee without reducing principal.
- Admin fee: One-time origination or document fee.
- Total fees: Sum of all periodic fees across periods plus admin fee.
- Total repayment: Principal plus total fees.
- Effective APR: Annualized percentage rate derived from the periodic fee and days.
- Cost per $100: Total fees divided by (principal/100).
How It Works: A Step-by-Step Example
Example: \(P=\$500\), \(f=\$15\) per \$100, \(d=14\) days, \(n=1\) rollover, \(A=\$0\).
Periodic fee: \(F = 500 \times \frac{15}{100} = \$75\). There are \(n+1=2\) periods, so total fees \(= 2 \times 75 = \$150\). Total repayment \(= 500 + 150 = \$650\). Effective APR (per 14-day period): \(\left(\frac{75}{500}\right) \times \frac{365}{14} \times 100 \approx 391\%\).
Frequently Asked Questions
Why is the effective APR so high?
Because the fee applies to a very short term. Annualizing a 14-day fee leads to a large APR even if the dollar fee seems small.
Do rollovers change the APR?
The per-period APR is tied to the term in days; rollovers increase total fees (and total cost) roughly linearly with each extra period.
Is compounding involved?
Typically no—fees are flat per period. This tool models linear fees plus optional fixed admin costs.
What’s not modeled?
Late fees, NSF fees, collection fees, wage-assignment costs, or state-specific caps are not included.
Where can I learn about protections?
See the CFPB’s consumer guide for payday loans for rights, alternatives, and complaint options.
Formula (LaTeX) + variables + units
\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100
Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
Audit: Complete 00 (e.g., \Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Audit: Complete 5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \
00 (e.g., \ Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
5 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\). Formula (LaTeX) + variables + units
This section shows the exact formulas used by the calculator engine, plus variable definitions and units.Formula (extracted LaTeX)\[\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100\]\text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100Formula (extracted text)\[\]Let: \(P\) = principal (loan amount) \(f\) = fee per \$100 (e.g., \$15 => \(f=15\)) \(d\) = term in days for one period \(n\) = number of rollovers \(A\) = one-time admin fee (optional) Periodic fee amount: \(\displaystyle F = P \times \frac{f}{100}\) Total fees (including rollovers): \(\displaystyle \text{Fees}_{\text{total}} = (n+1)\,F + A\) Total repayment (lump sum at final due date): \(\displaystyle \text{Repay} = P + \text{Fees}_{\text{total}}\) Effective APR (%), annualizing the periodic rate over days: \[ \text{APR}_{\%} = \left(\frac{F}{P}\right) \times \left(\frac{365}{d}\right) \times 100 \] Note: this is the single-period APR. With rollovers, total cost rises linearly with \((n+1)\), while APR per period remains tied to \(d\).Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
Variables and units
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
Sources (authoritative):
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/- Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/- Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance- Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt- Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization- Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff- APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr- Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparisonChangelog
Version: 0.1.0-draft
Last code update: 2026-01-190.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.
- P = principal (loan amount) (currency)
- r = periodic interest rate (annual rate ÷ payments per year) (1)
- n = total number of payments (years × payments per year) (count)
- M = periodic payment for principal + interest (currency)
- CFPB: Payday loans — consumerfinance.gov · Accessed 2026-01-19
https://www.consumerfinance.gov/consumer-tools/payday-loans/ - Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/ - Finance — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/finance - Loans & Debt — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/finance-loans-debt - Loan Amortization Schedule — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-amortization - Loan Payoff Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-payoff - APR Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/apr - Loan Comparison Tool — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/loan-comparison
Last code update: 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.