Auto Loan Calculator

Estimate your monthly car payment, amount financed, total interest, and overall cost. Ideal for car buyers, auto dealers, and financial planners seeking a precise, accessible, and mobile-first tool.

Loan Inputs

Choose down payment type
If checked, fees are included in the taxable amount.
Choose term units
Choose whether the number above is in months or years.

Results

Amount financed $0.00
Monthly payment $0.00
Total interest $0.00
Total of payments $0.00
Estimated sales tax $0.00
APR 0.00%
Term 0 months

Assumptions: fixed-rate amortizing loan with equal monthly payments. Results are estimates and may differ from lender offers.

The Formula Explained

Monthly payment (amortizing loan): \( \mathrm{PMT}=\dfrac{P \cdot i}{1-(1+i)^{-n}} \)

where \( P \) is amount financed, \( i=\text{APR}/12 \), \( n \) is months. For APR \( =0 \): \( \mathrm{PMT}=P/n \).

Amount financed with taxes and fees: \( P=(\text{Price}-\text{Down}-\text{TradeIn})+\text{Fees}+\text{Tax}_{\text{sales}} \).

Data Source and Methodology

Authoritative source: OpenStax, “Business Math,” Section 13.3 Annuities—Present Value and Payments, 2022. openstax.org.

All calculations are strictly based on the formulas and data provided by this source.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted text)
Monthly payment (amortizing loan): \( \mathrm{PMT}=\dfrac{P \cdot i}{1-(1+i)^{-n}} \) where \( P \) is amount financed, \( i=\text{APR}/12 \), \( n \) is months. For APR \( =0 \): \( \mathrm{PMT}=P/n \). Amount financed with taxes and fees: \( P=(\text{Price}-\text{Down}-\text{TradeIn})+\text{Fees}+\text{Tax}_{\text{sales}} \).
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn
, ', svg: { fontCache: 'global' } };

Auto Loan Calculator

Estimate your monthly car payment, amount financed, total interest, and overall cost. Ideal for car buyers, auto dealers, and financial planners seeking a precise, accessible, and mobile-first tool.

Loan Inputs

Choose down payment type
If checked, fees are included in the taxable amount.
Choose term units
Choose whether the number above is in months or years.

Results

Amount financed $0.00
Monthly payment $0.00
Total interest $0.00
Total of payments $0.00
Estimated sales tax $0.00
APR 0.00%
Term 0 months

Assumptions: fixed-rate amortizing loan with equal monthly payments. Results are estimates and may differ from lender offers.

The Formula Explained

Monthly payment (amortizing loan): \( \mathrm{PMT}=\dfrac{P \cdot i}{1-(1+i)^{-n}} \)

where \( P \) is amount financed, \( i=\text{APR}/12 \), \( n \) is months. For APR \( =0 \): \( \mathrm{PMT}=P/n \).

Amount financed with taxes and fees: \( P=(\text{Price}-\text{Down}-\text{TradeIn})+\text{Fees}+\text{Tax}_{\text{sales}} \).

Data Source and Methodology

Authoritative source: OpenStax, “Business Math,” Section 13.3 Annuities—Present Value and Payments, 2022. openstax.org.

All calculations are strictly based on the formulas and data provided by this source.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted text)
Monthly payment (amortizing loan): \( \mathrm{PMT}=\dfrac{P \cdot i}{1-(1+i)^{-n}} \) where \( P \) is amount financed, \( i=\text{APR}/12 \), \( n \) is months. For APR \( =0 \): \( \mathrm{PMT}=P/n \). Amount financed with taxes and fees: \( P=(\text{Price}-\text{Down}-\text{TradeIn})+\text{Fees}+\text{Tax}_{\text{sales}} \).
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn
]], displayMath: [['\\[','\\]']] }, svg: { fontCache: 'global' } };, svg: { fontCache: 'global' } };

Auto Loan Calculator

Estimate your monthly car payment, amount financed, total interest, and overall cost. Ideal for car buyers, auto dealers, and financial planners seeking a precise, accessible, and mobile-first tool.

Loan Inputs

Choose down payment type
If checked, fees are included in the taxable amount.
Choose term units
Choose whether the number above is in months or years.

Results

Amount financed $0.00
Monthly payment $0.00
Total interest $0.00
Total of payments $0.00
Estimated sales tax $0.00
APR 0.00%
Term 0 months

Assumptions: fixed-rate amortizing loan with equal monthly payments. Results are estimates and may differ from lender offers.

The Formula Explained

Monthly payment (amortizing loan): \( \mathrm{PMT}=\dfrac{P \cdot i}{1-(1+i)^{-n}} \)

where \( P \) is amount financed, \( i=\text{APR}/12 \), \( n \) is months. For APR \( =0 \): \( \mathrm{PMT}=P/n \).

Amount financed with taxes and fees: \( P=(\text{Price}-\text{Down}-\text{TradeIn})+\text{Fees}+\text{Tax}_{\text{sales}} \).

Data Source and Methodology

Authoritative source: OpenStax, “Business Math,” Section 13.3 Annuities—Present Value and Payments, 2022. openstax.org.

All calculations are strictly based on the formulas and data provided by this source.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted text)
Monthly payment (amortizing loan): \( \mathrm{PMT}=\dfrac{P \cdot i}{1-(1+i)^{-n}} \) where \( P \) is amount financed, \( i=\text{APR}/12 \), \( n \) is months. For APR \( =0 \): \( \mathrm{PMT}=P/n \). Amount financed with taxes and fees: \( P=(\text{Price}-\text{Down}-\text{TradeIn})+\text{Fees}+\text{Tax}_{\text{sales}} \).
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn