Loan amortization schedule generator

How it works

An amortizing loan is repaid through constant monthly payments that combine, each month, an interest portion (calculated on the remaining balance) and a principal portion. This tool calculates the monthly payment using the standard amortization formula, then reconstructs month by month the interest/principal split and the change in the remaining balance until the loan is fully repaid.

Why does the interest portion decrease over time?

At the start of the loan, the remaining balance is high, so interest (proportional to this balance) is also high, and the principal portion repaid in the payment is small. Month after month, the remaining balance decreases, so interest decreases too and a growing share of the payment goes toward repaying the principal.

What does a monthly extra repayment change?

By adding a fixed amount to each payment, you reduce the remaining balance faster: the actual loan duration shortens and the total interest paid decreases, even though the displayed base payment stays the same. The table above accounts for this effect in the effective number of payments and the total cost.

This simulation is a simplified estimate at a fixed rate, without additional fees (insurance, guarantee, application fees); it does not replace a detailed loan offer nor the advice of a financial advisor, broker or banker.

The calculation is done entirely in your browser: the amount, rate and duration entered are never sent to a server.