Amortization Schedule Calculator
Each row is one month: what went to interest, what actually reduced the balance, and what you still owe.
Written for Equidwell and last checked in October 2026. We build the calculators on this site. We are not a lender, and this page is not advice for your loan.
How this calculator works
- Each month, interest is the remaining balance times the monthly rate.
- The rest of the scheduled payment reduces principal.
- An extra amount you enter is applied to principal and can shorten the schedule.
- The final contractual payment absorbs leftover cents so the balance ends at zero.
Why the early payments feel like they do so little
Early on, the balance is still huge, so interest takes most of a payment that never changes size. Principal gets the leftover. That is why year one feels like you are treading water.
The yearly chart is that shift without 360 rows. Later years put more of the same payment onto principal, as long as the rate stays put and nobody recasts the loan.
Sources
Common questions
Can I download the schedule?
Yes. The CSV is the full monthly schedule, even if the table on screen is showing yearly totals.
Does extra payment reduce interest?
In this model, yes. The result shows interest saved and months saved against the same loan with no extra payment.
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Longer guides on these topics are linked from the guides library.