Calculator
Amortization Schedule Calculator, by Month and Year
See where every payment goes, month by month, and why the early years are mostly interest.
What changed
- : First published.
How to use it
Enter the loan amount (the amount borrowed, not the home price), the interest rate, the term and the month of your first payment. You will see the monthly principal and interest payment, total interest, the payoff month, a year-by-year summary and, if you open it, every single payment.
How amortization works
A fixed-rate mortgage has the same principal and interest payment every month. What changes is the split:
- Interest for the month = balance × (annual rate ÷ 12).
- Principal for the month = payment − interest.
- New balance = old balance − principal.
Repeat that 360 times and the balance reaches zero on the final payment. The payment itself comes from the formula M = P × r ÷ (1 − (1 + r)−n), which is the one level payment that makes those steps end at exactly zero.
Worked example: $320,000 at 6.5% for 30 years
The payment is $2,022.62. In month 1, interest is 320,000 × 0.065 ÷ 12 = $1,733.33, so principal is $2,022.62 − $1,733.33 = $289.28 (rounded), leaving $319,710.72. Month 2's interest is a little lower, $1,731.77, so principal rises to $290.85. In the first year you pay about $20,695 in interest and $3,577 in principal. Principal first exceeds interest at payment 233, more than 19 years in, and half the loan is repaid only at payment 257.
The schedule at a glance
| After | Balance left on $320,000 at 6.5% |
|---|---|
| 1 year | about $316,423 |
| 5 years | about $299,555 |
| 10 years | about $271,284 |
| 30 years | $0 |
Total interest over 30 years is about $408,142, more than the amount borrowed. The same loan over 15 years has a payment of $2,787.54 but total interest of about $181,758.
Why this matters
- Selling or refinancing early. If you sell after five years, most of what you paid went to interest, and you still owe about 94% of the original loan in this example.
- Extra payments. Any extra principal skips ahead on the schedule and removes all the interest that balance would have cost. The extra payment calculator shows the effect.
- PMI removal. Conventional PMI ends when the scheduled balance reaches 78% of the original value. The schedule tells you roughly when that will be.
- Compare with your Loan Estimate. The CFPB's Loan Estimate shows projected payments and total interest percentage, which you can check against this schedule.
Limits
This schedule assumes a fixed rate and payments made in full on the due date. Adjustable-rate loans recalculate at each adjustment. Your servicer rounds each month to the cent, so the last payment may differ by a few cents. The rate box starts at Freddie Mac's dated weekly average; replace it with your own rate.
Common questions
Why does so little of my payment go to principal at first?
Interest is charged on the balance, and the balance is largest at the start. As the balance falls, each month's interest falls too, so more of the same fixed payment goes to principal.
Can I download the schedule?
Open "Every payment" to see all rows; you can copy the table into a spreadsheet. Nothing is sent to a server.
Does the schedule include taxes and insurance?
No. Amortization covers principal and interest only. Escrow amounts for taxes and insurance are added on top and change over time.
Sources
- CFPB, What is a prepayment penalty?
- CFPB, What is a Loan Estimate?
- Freddie Mac, Primary Mortgage Market Survey (PMMS)
Checked Nov 11, 2026. Spot an error? Tell us.