Amortization schedule calculator
Enter the loan, rate and term to get the payment and a year-by-year schedule, then add an extra monthly amount to see how much sooner it's gone.
Your monthly payment
$2,022.62
$408,140.64 in interest over 30 yr 0 mo
How to use it
- Enter the amount borrowed, the rate and the term in years.
- Read the monthly payment and the yearly rows: interest paid, principal paid and the balance left at the end of each year.
- Add an extra monthly payment to see the new payoff time and the interest it saves.
Worked example
$320,000 at 6.5% over 30 years. The payment is $2,022.62.
Month one: interest is $320,000 × 0.5417% = $1,733.33, so only $289.29 goes to principal. After year one the balance is $316,423.24; after year 15 it’s $232,188.56. Total interest over the loan is $408,140.64.
Adding $200 a month pays it off in 23 years 5 months and saves $105,427.85 in interest.
How this is calculated
The monthly payment is the level payment for the loan, rate and term. Each month the balance earns interest at the yearly rate divided by 12, rounded to the cent, and whatever is left of the payment plus your extra amount goes to principal. The schedule is built month by month the way a servicer books it, the yearly rows add those months up, and the final payment is trimmed to what's still owed, so the totals are exact rather than payment × months.
monthly payment = loan × r × (1 + r)ⁿ ÷ ((1 + r)ⁿ − 1), with r the monthly rate and n the number of payments
Each month: interest = balance × r, rounded to the cent; principal = payment + extra − interest; balance = balance − principal
The schedule is built month by month with cent rounding, the way a servicer books it, and the yearly rows add those months up. The final payment is trimmed to whatever is still owed, so the totals are exact rather than payment × months.
Rates, sources and limits
Estimates only. Servicers may round differently or apply extra payments on different dates. Not financial advice.
Last reviewed 13 Sep 2026 by the CalcRabbit team. Estimates only, not financial, tax or medical advice.
Frequently asked questions
Why does so little go to principal at first?
Interest is charged on the whole balance each month, and the balance is largest at the start. As it falls, the same payment covers less interest and more principal. On a 30-year loan the split doesn't reach half and half until around year 19.
Do extra payments really help?
Every extra dollar goes to principal, so it stops earning interest for the lender immediately. On the example above, $200 a month saves about $105,000 and more than six years. Check that your lender applies extras to principal rather than to next month's payment.
Why is total interest slightly different from payment × months − loan?
Because the schedule rounds interest to the cent each month, and the last payment is smaller than the rest. The difference is usually under a dollar. This calculator reports the exact schedule total.
Can I use this for a car loan or personal loan?
Yes. Any fixed-rate, level-payment loan amortizes the same way. Enter the term in years; for a 48-month car loan that's 4.