Calculate your monthly payment, total interest, and full repayment breakdown for any loan.
Also calculate percentages with the Percentage Calculator or tips with the Tip Calculator.
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This loan calculator works as a mortgage payment calculator, car loan calculator, and amortization calculator for anyone who needs to understand the cost of borrowing before taking on debt. Enter any loan amount, interest rate, and term to instantly see the monthly payment, total amount paid over the life of the loan, and total interest cost.
Monthly loan payments use the standard amortization formula: M = P[r(1+r)ⁿ] / [(1+r)ⁿ − 1], where P is the principal loan amount, r is the monthly interest rate (annual rate divided by 12), and n is the total number of monthly payments. This formula produces a fixed monthly payment that gradually shifts from being mostly interest in the early months to being mostly principal in the later months — a process called amortization.
Understanding amortization helps borrowers make better decisions. For a $300,000 mortgage at 6% over 30 years, the monthly payment is $1,799, but the total paid over 30 years is $647,515 — more than double the original loan amount. Shortening the term to 15 years raises the monthly payment to $2,532 but reduces total interest from $347,515 to just $155,726. Knowing these numbers before committing to a loan helps compare options, plan budgets, and decide whether to make extra payments to reduce the principal faster. This calculator is for educational and estimation purposes — always consult a licensed financial advisor or lender for actual loan decisions.
For car loans and personal loans — which typically have shorter terms of 3 to 7 years — the total interest paid is a smaller proportion of the principal than for a mortgage, but the interest rate is often higher. A $20,000 car loan at 8% over 5 years results in a monthly payment of $406 and total interest of $4,332. Changing the rate to 5% reduces total interest to $2,645 — a $1,687 saving over the life of the loan. Running these comparisons before accepting a loan offer is one of the most practical uses of this calculator.