Watch a loan being paid off year by year. Enter the amount, rate and term to see the monthly payment plus a yearly table of interest paid, principal repaid and the remaining balance.
Amortization Calculator
How the Amortization Calculator Works
This calculator builds the full repayment schedule for a loan — every monthly payment, split into interest and principal, from the first payment to the last. While the loan and mortgage calculators show the totals, this one shows the journey: how much of each payment goes to interest, how the balance shrinks, and when the balance tips from mostly interest to mostly principal.
The monthly payment uses the standard formula: M = P × r(1 + r)^n ÷ ((1 + r)^n − 1). P is the loan amount, r is the monthly rate (annual rate divided by 100, then by 12), n is the number of payments, and M is the fixed payment. The schedule then works month by month: interest for the month = remaining balance × r; principal for the month = M − interest; and the balance falls by the principal part. Repeating that until the balance reaches zero produces the table.
The schedule assumes a fixed rate, payments on the same day each month, and no extra payments, fees, or rate changes. If you make extra payments in real life, the schedule shortens and later rows change — but the opening rows and the payment amount stay exactly as shown.
How to Use This Calculator
- Enter the total loan amount.
- Enter the annual interest rate.
- Enter the loan term in years.
- Press Calculate.
- Read the monthly payment and totals, then scroll through the schedule to see how each payment is split and when the balance falls fastest.
Example
A $10,000 loan at 6% over 3 years has a monthly payment of $304.22 and total interest of $951.90. The first payment of $304.22 is $50.00 interest and $254.22 principal, leaving $9,745.78. The last payment is $1.52 interest and $302.70 principal, leaving zero.
Notice how the split changes: in month 1, interest is 16% of the payment; by the final month it is under 1%. Over the first year you pay $538.13 in interest, but in the final year only $103.39 — because the balance, and therefore the interest charged on it, has shrunk so much.
What Affects the Result
- Interest rate — a higher rate raises the early interest share and the total interest.
- Loan term — longer terms spread the principal thinner, so interest dominates for longer.
- Loan amount — the schedule scales with the amount borrowed.
- Extra payments — paying extra attacks the principal directly and pulls later interest down.
- Practical tip — look at the schedule’s halfway point: if you are still paying mostly interest there, a shorter term or a lower rate would help a lot.
The schedule also makes clear why the first years of a long loan can feel like treading water. On a $200,000 mortgage at 6% over 30 years, the monthly payment is $1,199.10, and the first payment is $1,000.00 of interest and only $199.10 of principal. After five years of payments — $71,946 paid in — the balance has fallen by just $15,800, to $184,200; the other $56,146 went to interest. That is not a mistake or a trick; it is how amortization works when the balance is large and the rate is applied monthly. Knowing this in advance changes how people think about extra payments: an additional $200 a month from the start of that mortgage would cut the term by more than six years and save over $47,000 in interest, because every extra dollar goes straight to principal and shrinks every future interest charge. If you only ever look at the monthly payment, that opportunity stays invisible; the schedule shows it.
Another useful habit is to check the schedule before refinancing. Refinancing restarts the amortization clock, which means your payments go back to being mostly interest even if the rate is lower. Whether that trade is worth it depends on the numbers: compare the remaining interest on your current schedule against the total interest on the new one, not just the monthly payment. A lower payment on a fresh 30-year schedule can cost more overall than a higher payment with ten years left on the original loan.
Amortization Calculator FAQs
What is amortization?
Amortization is the process of paying off a loan through regular payments, where each payment covers that month’s interest and reduces the principal. The schedule shows exactly how each payment is split.
Why is the interest share higher at the start?
Interest is charged on the outstanding balance, which is largest at the beginning. As you repay principal, the balance and the interest on it both shrink, so more of each payment goes to principal.
Does the payment ever change?
Not on a fixed-rate loan — the payment stays the same throughout. Only the split between interest and principal changes. On a variable-rate loan, the payment would be recalculated when the rate changes.
Can I see the schedule for part of the loan?
The calculator shows the full schedule from the first to the last payment. For a long loan this can be many rows, but it lets you find any point — for example, the balance after five years.
What happens if I make an extra payment?
The extra amount reduces the principal immediately, which lowers all future interest charges and shortens the loan. This calculator assumes the standard schedule without extras, so treat any extra payment as an improvement on these figures.
Related calculators: Mortgage Calculator, Loan Calculator, Interest Rate Calculator.