Student Loan Payoff Calculator: Time and Interest to Clear It
See how long a student loan takes to clear at a chosen monthly payment, and how much interest a larger payment would save.
Adjust the inputs and select Calculate for a full breakdown.
Year-by-year payoff schedule
Compare Common Scenarios
How the numbers shift across typical situations for this calculator:
| Scenario | Time to pay off | Total interest | Total paid |
|---|---|---|---|
| $35k · 6.5% · $400/mo | 9y 11m | $12,565.36 | $47,565.36 |
| $20k · 5.5% · $300/mo | 6y 8m | $3,922.34 | $23,922.34 |
| $60k · 7% · $700/mo | 10 years | $23,420.32 | $83,420.32 |
| $12k · 4.5% · $250/mo | 4y 6m | $1,254.86 | $13,254.86 |
How This Calculator Works
Enter the loan balance, its interest rate, and the monthly payment you plan to make. The calculator works month by month — adding interest, subtracting the payment — until the balance clears, then reports the payoff time and the total interest.
The Formula
Debt Payoff Time
B = balance, P = fixed monthly payment, r = monthly rate (APR ÷ 12), n = months to clear
Worked Example
A $35,000 student loan at 6.5% paid at $400 a month clears in 119 months — just under ten years. Interest over that time comes to about $12,565, on top of the amount borrowed.
Key Insight
Extra payments applied to principal shorten a student loan sharply, because the remaining balance accrues less interest every month after. Confirm with the servicer that overpayments reduce principal, not future installments.
Frequently Asked Questions
How can I pay off a student loan faster?
Raise the monthly payment, and direct any extra to principal. A larger payment cuts both the payoff time and the total interest noticeably.
Does this model income-driven repayment?
No. Income-driven plans set the payment from income rather than the balance. This calculator assumes a fixed monthly payment, suiting standard or accelerated repayment.
Should I pay extra or invest instead?
Compare the loan rate against the return you could expect investing. Paying down a high-rate loan is a guaranteed return; a low-rate loan is a closer call.
Will extra payments go to principal?
Not automatically. Some servicers apply overpayments to future installments. Instruct the servicer to apply anything extra to the principal balance.
What balance should I enter?
Use the current outstanding balance, including any capitalized interest, so the payoff time is measured from where the loan stands today.
Related Calculators
Data Sources & Benchmarks
This calculator draws on 3 independent, dated sources.
Methodology & Review
The payoff is simulated month by month from the current balance: interest is charged, the fixed payment is deducted, and months are counted until the balance clears. Income-driven plans are not modeled.
Written by Ugo Candido · Last updated May 17, 2026.