FREE CALCULATOR · MONEY
See your monthly payment, total interest, and the true lifetime cost of a loan before you sign — works for car loans, personal loans, student loans, and mortgages.
Enter the amount you borrow, the annual rate, and the term.
Three numbers decide what a loan costs you: how much you borrow, the annual interest rate (APR), and how long you take to pay it back. This calculator turns those three into the two numbers that matter — the monthly payment and the total interest you'll hand over.
Each month, your payment first pays that month's interest — the remaining balance times the monthly rate — and whatever is left chips away at the balance. Early on, the balance is large, so most of each payment is interest; near the end, it's mostly principal. That's amortization, and it's why your first payment feels so different from your last.
A $25,000 car loan at 6.5% APR paid over 5 years: the monthly rate is about 0.00542, there are 60 payments, and the formula gives a monthly payment of $489.15. Over 5 years you pay $29,349.22 total — $4,349.22 of that is interest.
Lenders use the amortization formula: the loan amount is multiplied by the monthly interest rate and divided by one minus (1 + monthly rate) raised to the negative number of payments. That gives the fixed payment that pays the loan off exactly by the last month.
Multiply the monthly payment by the number of months, then subtract the amount you borrowed. The difference is your total interest. On the example above — $489.15 × 60 − $25,000 — that's $4,349.22.
Interest each month is charged on the balance you still owe. At the start the balance is highest, so interest takes the biggest bite. As you pay the balance down, the interest portion shrinks and more of each payment goes to principal.
Extra money goes straight to the principal, which shrinks the balance faster and cuts the total interest. Even a small extra amount each month can save thousands on a long loan — though some loans charge a prepayment penalty, so check your terms first.
A shorter term means a higher monthly payment but much less total interest. A longer term lowers the payment but raises the interest you pay over time. The right choice depends on what monthly payment you can comfortably afford.
APR (annual percentage rate) includes the interest rate plus most lender fees, spread over the loan's term. It's the fairer number for comparing loan offers, because two loans with the same interest rate can have different APRs once fees are included.
No. It covers principal and interest only. Car loans add fees and taxes; mortgages add property tax, insurance, and sometimes mortgage insurance. Factor those in separately for the full monthly cost.