How amortization schedule generator works
An amortization schedule is the month-by-month breakdown of a fixed-rate loan showing how each payment splits between interest and principal until the balance reaches zero. This generator builds the full table from your principal, annual interest rate, and term (or your exact monthly payment), so you can see exactly where every dollar of each payment goes.
Each month the calculator accrues interest on the remaining balance at the monthly rate (annual rate divided by 12), then applies your scheduled payment. The payment first covers that month's interest and the remainder reduces principal. Early in the loan almost all of each payment is interest; near the end almost all is principal. An optional extra monthly payment is applied entirely to principal and shortens the schedule.
The level monthly payment is derived from the standard amortization formula M = P × r × (1+r)^n / ((1+r)^n − 1), where P is the principal, r is the monthly rate, and n is the number of payments. At 0% interest it simply divides the principal by the number of payments. Optional start and end dates produce a payoff date. This is a planning estimate for a fixed-rate loan and does not model escrow, taxes, insurance, or rate changes.