What is an amortization schedule?
An amortization schedule is a table that breaks every loan payment into interest and principal, and shows the remaining balance after each payment. It is the exact schedule your lender uses to pay off the loan over time.
The schedule shows why extra payments early in the loan are so powerful: the balance is highest at the start, so every dollar of principal retired early avoids the most interest.
How to read the table
Each row shows one month: the payment number, the interest charged that month, the portion of the payment that reduced principal, and the remaining balance. The last row shows the payoff month, when the balance reaches zero.
If you add an extra principal payment, the table shortens. This calculator shows both the standard schedule and the schedule with extra payments side by side.
Why the principal grows and interest shrinks
Interest is calculated on the current balance. As the balance falls, the monthly interest charge falls too. Because the payment is fixed, the portion going to principal grows each month. Early payments are mostly interest; late payments are mostly principal.
How to use the schedule to plan extra payments
Add an extra monthly amount to see how many rows drop off the schedule. The table shows the new payoff month and the total interest saved. The earlier you start, the more rows — and more interest — you eliminate.
Common mistakes
Forgetting that the schedule applies to principal and interest only. Escrow, taxes, and insurance are separate. Also, variable-rate loans change over time, so the schedule is accurate only for the current fixed rate.