Short answer: this loan calculator shows your monthly payment, the total interest over the life of the loan, and your payoff date — plus what an extra monthly payment saves you. Example: $25,000 at 7.5% for 5 years costs $500.95 a month and $5,057 in total interest.
| Total interest | — |
| Total cost of the loan | — |
| Payoff date | — |
| With extra payments: interest saved / months cut | — |
See the full breakdown
Educational estimate only — not financial advice and not a loan offer. Assumes a fixed rate, monthly payments on time, and no fees or prepayment penalties. Your lender’s APR includes fees, so a payment computed from APR will differ slightly from one computed from the note rate.
How this calculator works
It uses the standard amortization formula — payment = r × P ÷ (1 − (1 + r)^−n), where P is the amount borrowed, r is the monthly rate (annual rate ÷ 12), and n is the number of monthly payments — then simulates the loan month by month so the interest total and the extra-payment comparison are exact within the model. Early payments are mostly interest; later payments are mostly principal. That split is why extra payments early in the loan save the most.
Worked example
- $25,000 at 7.5%, 5 years → payment $500.95, total interest $5,057, total cost $30,057.
- Add $100/month extra → interest falls to $4,043 (saving $1,014) and the loan ends 11 months early.
- Big-loan check: $100,000 at 6% for 15 years → $843.86/month, $51,894 interest.
FAQs
What's the difference between the interest rate and APR? APR folds in lender fees, so it runs slightly higher. If you enter APR here, the payment will be a touch higher than your actual note payment — the total-cost picture is the more honest one. Does paying extra always help? It always reduces interest on a simple amortizing loan; just confirm your loan has no prepayment penalty (most consumer loans don't). Why is so much of my first payment interest? Interest is charged on the outstanding balance, which is largest at the start. The breakdown table shows the balance — and the interest share — shrinking every year.
Sources: CFPB: what is amortization?, FRED TERMCBPER24NS (24-month personal loan rate) Figures last verified Report a wrong number