Estimate your monthly loan payment in seconds. This free loan calculator works for personal, auto, student and home-improvement loans — enter your loan amount, interest rate and term to see your total interest, payoff date, and how much an extra payment could save you.
Results update automatically as you type. Estimates only — confirm exact figures with your lender.
How Loan Calculator Works
A loan payment is the fixed amount that fully repays a borrowed sum, plus interest, across a set number of months. The loan calculator applies the standard fixed-rate amortization formula to your loan amount, rate and term to find that monthly figure, then layers in any extra payment you enter to show how much faster you’d pay it off.
Formula: M = P × [r(1+r)^n] / [(1+r)^n − 1]
- M — the scheduled monthly payment
- P — the loan amount you’re borrowing
- r — the monthly interest rate (annual APR ÷ 12 ÷ 100)
- n — the total number of payments (loan term converted to months)
- Extra payment — an optional amount added to M each month, which the calculator simulates against the declining balance to find a shorter real payoff time and lower total interest
Example Scenarios
| Loan Amount | Rate (APR) | Term | Monthly Payment |
|---|---|---|---|
| $8,000 | 9.0% | 2 yr | $365 |
| $10,000 | 6.0% | 3 yr | $304 |
| $15,000 | 5.0% | 4 yr | $345 |
| $25,000 | 7.5% | 5 yr | $501 |
| $40,000 | 8.0% | 6 yr | $701 |
Loan Calculator FAQ
How much interest does an extra monthly payment actually save?
Any extra amount goes straight to reducing principal rather than interest, so each dollar of overpayment shrinks the balance interest is charged on for every remaining month. The calculator simulates this month by month to show the real interest saved and how much sooner the loan is paid off.Does this loan calculator work for auto, personal, and student loans?
Yes — the amortization math is identical for any fixed-rate installment loan. Enter the loan amount, APR, and term in years or months and the calculator returns the same monthly payment, total interest, and payoff date regardless of the loan type.What’s the difference between entering the term in years versus months?
They produce the same result — the calculator just converts years to months internally (years × 12) before running the payment formula. Use whichever unit matches how your lender quotes the term.Why is my total interest so much higher than the loan amount on a long term?
Interest is charged on the outstanding balance every month, so stretching a loan over more months means more months of interest accrual even though each payment is smaller. A longer term always increases total interest paid unless the rate drops significantly.How is the monthly payment calculated when there’s no extra payment?
The calculator uses the standard amortization formula, which spreads the loan amount into equal monthly payments that cover both accruing interest and a portion of principal, so the balance reaches exactly zero at the end of the term.What happens if I enter an extra payment larger than the interest owed?
The simulation reduces principal by the extra payment each month, which shortens the loan. If the extra payment plus scheduled payment would overpay the remaining balance, the calculator caps the payoff at the loan’s natural term.Related Calculators
If your loan is specifically for a vehicle, the auto loan calculator adds trade-in and sales-tax fields to the same amortization math. Carrying balances across several loans or cards? You can also compare the payment on a single consolidation loan or pull up a full month-by-month amortization schedule for this loan.