Student Loan Payoff Calculator
See how paying extra each month gets you out of student debt faster and cuts total interest.
Want to understand the concept, not just the number? Read Debt Snowball vs Avalanche .
| Year | Principal paid | Interest paid | Balance |
|---|---|---|---|
| 1 | $3,492 | $1,705 | $26,508 |
| 2 | $3,707 | $1,490 | $22,801 |
| 3 | $3,936 | $1,261 | $18,865 |
| 4 | $4,178 | $1,018 | $14,687 |
| 5 | $4,436 | $761 | $10,251 |
| 6 | $4,710 | $487 | $5,541 |
| 7 | $5,000 | $196 | $541 |
| 8 | $541 | $3 | $0 |
How it's calculated
The loan is simulated month by month with your extra payment applied straight to principal, then compared against the standard schedule. The gap between the two is the interest and time you save.
Extra principal helps because it shrinks the balance that interest is charged on for the rest of the loan. Paying even $100 more a month on a typical balance can shave a year or more off the term and save a meaningful amount of interest.
The higher your rate and the earlier you start, the bigger the effect. On private loans this is almost always worth it. On federal loans, weigh it against the protections you would keep by staying on the standard plan.
Assumptions
- Extra payments apply entirely to principal from the first payment.
- A fixed rate for the full term, compounded monthly.
Last updated: 2026-08-07
These assumptions follow our general methodology.
Frequently asked questions
Should I refinance instead?
Refinancing can lower your rate, but federal loans lose protections like income-driven repayment and forgiveness. Weigh both before you refinance federal debt.
Is there a downside to paying student loans off early?
The main tradeoff is giving up cash you could invest or save elsewhere. If your loan rate is low, investing might come out ahead. If it is high, paying it down is a guaranteed return equal to the rate.
Do extra payments go to interest or principal?
Tell your servicer to apply extra payments to principal. Otherwise they may treat it as an early payment of future interest, which does not shorten the loan.