Loan Calculator
Find the regular payment on any fixed-rate loan and see exactly how much interest you will pay over its life.
🔒 Runs entirely in your browser. Nothing you enter is sent to a server.
Before you sign for a personal loan, car loan or business loan, you should know two numbers: how much you will pay each period, and how much the loan will cost you in total. This calculator shows both for any fixed-rate loan, with monthly, biweekly or weekly payment schedules.
How to use the loan calculator
- Enter the loan amount, the amount you are borrowing.
- Enter the annual interest rate from your loan offer.
- Set the term in years, plus any extra months.
- Pick a payment frequency.
The results update instantly. Try different terms to see how a shorter loan raises the payment but saves interest.
The loan payment formula
Fixed-rate installment loans are amortizing. Each payment covers that period’s interest first, and the rest reduces the balance. The payment is:
Payment = P × r ÷ (1 − (1 + r)^−n)- P is the principal, the amount borrowed
- r is the interest rate per period (annual rate ÷ payments per year)
- n is the total number of payments
Worked example
A $25,000 loan at 8% for 5 years, paid monthly:
- r = 0.08 ÷ 12 ≈ 0.006667, and n = 60
- Payment = 25,000 × 0.006667 ÷ (1 − 1.006667^−60) ≈ $506.91 a month
- Total repaid ≈ $30,414, so total interest is about $5,415
How term length changes the cost
The same $25,000 loan at 8%:
| Term | Monthly payment | Total interest |
|---|---|---|
| 3 years | $783.41 | $3,203 |
| 5 years | $506.91 | $5,415 |
| 7 years | $389.66 | $7,731 |
A longer term lowers the monthly payment, but you pay interest for longer. Going from 3 to 7 years more than doubles the interest here.
Tips to borrow for less
- Check your credit report first and fix any errors. A better score is the single biggest lever on your rate.
- Get pre-qualified with several lenders. A soft credit check doesn’t hurt your score.
- Choose the shortest term you can comfortably afford. Leave room in your budget for emergencies.
- Watch for fees. An origination fee of 1–8% may be taken off the money you receive, so compare APRs, not just rates.
- Pay extra when you can. Even rounding a $506.91 payment up to $550 takes several months off a 5-year loan.
Frequently asked questions
What is the difference between interest rate and APR?
The interest rate is the cost of borrowing the principal. APR (annual percentage rate) also includes fees such as origination charges, spread over the loan's life. Use the interest rate here to calculate payments, and compare APRs when you shop between lenders.
Do biweekly payments save money?
Paying every two weeks gives you 26 half-payments a year, the same as 13 monthly payments instead of 12. That extra payment shortens the loan and cuts interest, as long as the lender applies the payments to principal right away.
Does this calculator work for car loans and student loans?
Yes. Any fixed-rate installment loan with equal regular payments uses the same formula, including personal, auto, student, business and boat loans. It doesn't fit credit cards or variable-rate loans, where the payment changes over time.
Can I pay off my loan early?
Usually yes, and doing so saves interest. Check your agreement for prepayment penalties first. When you make extra payments, ask the lender to apply them to principal rather than to future payments.