About the Amortization Schedule Calculator
This amortization schedule calculator turns a loan amount, interest rate and term into a complete payment table. For every payment it shows how much goes to interest, how much reduces the principal and what balance remains, along with the payment date and the date the loan will be paid off.
Use it for a mortgage, auto loan, personal loan or any fixed-rate installment loan. Switch between a yearly summary and a month-by-month view (120 payments at a time, starting from any year you choose), and add an optional extra monthly principal payment to see how much sooner the loan ends and how much interest you avoid.
The schedule assumes a fixed rate, monthly payments and interest charged on the outstanding balance each month, which is how standard US mortgages and most installment loans are amortized. Figures are rounded for display; your servicer’s schedule may differ by a few cents because of rounding each payment.
With the default inputs, the monthly payment is $1,769.79. Change any value above to recalculate instantly.
How to use the amortization schedule calculator
- 1Enter the loan amount, annual interest rate and term in years.
- 2Optionally add an extra monthly principal payment.
- 3Set the date of your first payment to get dated rows and a payoff date.
- 4Choose the yearly summary or the monthly view, and pick the starting year for monthly rows.
- 5Read the chart to see when principal overtakes interest.
Formula and method
The level payment M comes from the standard amortization formula, where P is the amount borrowed, r is the monthly rate (annual rate ÷ 12) and n is the number of months. Each month, interest Iₖ is the previous balance times r; the rest of the payment, plus any extra principal E, reduces the balance.
Because interest is charged on a shrinking balance, the interest share of each payment falls every month while the principal share grows. With extra payments the balance reaches zero before n months; the final payment is only what is needed to clear the remaining balance plus its interest.
- M
- Scheduled monthly payment (principal + interest)
- P
- Original loan amount
- r
- Monthly interest rate (annual % ÷ 12 ÷ 100)
- n
- Number of monthly payments (years × 12)
- E
- Optional extra principal paid each month
- Bₖ
- Balance after payment k
Worked examples
$280,000 mortgage at 6.5% for 30 years
A $280,000 loan at 6.5% for 30 years has a payment of $1,769.79. Over 360 payments you pay about $357,125 in interest, so the total is roughly $637,125. The first payment in January 2026 means the last one is due December 2055.
$25,000 car loan at 7.9% for 5 years
A five-year $25,000 loan at 7.9% costs $505.71 a month. Across 60 payments the interest adds up to about $5,343, and the monthly view lists every payment.
Adding $300 a month extra to a $280,000 loan
Adding $300 of principal every month to the $280,000, 6.5% loan retires it in 245 payments instead of 360 — 9 years and 7 months sooner — and cuts total interest from about $357,125 to about $225,613.
Frequently asked questions
What is an amortization schedule?+
It is a table listing every loan payment with the split between interest and principal and the balance left afterwards. It shows exactly how a fixed payment gradually pays the loan to zero over the term.
Why do I pay so much interest at the start?+
Interest is charged on the outstanding balance, which is largest at the start. Early payments are therefore mostly interest; as the balance shrinks, more of each identical payment goes to principal.
How do extra payments change the schedule?+
Extra principal lowers the balance immediately, so every later payment carries less interest. The scheduled payment stays the same, but the loan ends earlier and total interest drops — often by tens of thousands of dollars on a mortgage.
Does the schedule include taxes and insurance?+
No. An amortization schedule covers principal and interest only. Property tax, homeowners insurance and PMI collected through escrow are added on top of this payment by your servicer.
Why does my lender’s schedule differ slightly?+
Servicers round each payment and interest charge to the cent, and some count interest by days in the month. That can shift figures by a few cents per payment and a small amount on the final payment.
Results are estimates for educational purposes and are not financial advice. Rates, fees and terms vary — confirm with your lender or a licensed advisor before making decisions.