Amortization Calculator
See every payment on a loan split into interest and principal, with the balance after each one. Add an extra monthly payment to see how much sooner you finish and how much interest you save. It runs in your browser.
Also searched as: amortization schedule calculator · loan amortization calculator · mortgage amortization calculator · extra payment calculator
Updated November 9, 2026
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How to use it
- 1
Enter the loan
Type the amount, the yearly interest rate and the term in years.
- 2
Add extra payments
Enter any extra amount you could pay each month.
- 3
Read the schedule
See the yearly summary, or tick the box for every month.
Questions about amortization calculator
What is an amortization schedule?
A table of every payment on a loan, showing how much goes to interest, how much repays the amount borrowed, and what you still owe afterwards.
How do extra payments help?
Extra money goes straight to the balance, so the interest in later months is lower and the loan ends sooner. The tool shows the time and interest saved.
Can I see every month?
Yes. Tick the box to switch from a yearly summary to the full month-by-month schedule.
How each payment is split
Interest is charged on the balance you still owe, so early payments are mostly interest. On a 300,000 loan at 6.5% over 30 years the payment is 1,896.20. In the first month 1,625.00 of it is interest and only 271.20 repays the loan. As the balance falls, the interest share shrinks and the principal share grows, while the payment stays the same.
Over the whole loan you pay 382,633.47 in interest. The table shows the same loan year by year.
| Year | Interest paid | Principal repaid | Balance at year end |
|---|---|---|---|
| 1 | 19,401 | 3,353 | 296,647 |
| 5 | 18,409 | 4,346 | 280,833 |
| 10 | 16,745 | 6,009 | 254,328 |
| 15 | 14,445 | 8,310 | 217,677 |
| 20 | 11,263 | 11,491 | 166,996 |
| 25 | 6,864 | 15,890 | 96,912 |
| 30 | 781 | 21,973 | 0 |
What an extra payment does
An extra amount goes straight to the balance, so every later month has less interest. Adding 200 a month to the same loan ends it after 23 years 1 month instead of 30 years, and cuts the total interest from 382,633.47 to 279,184.67, a saving of 103,448.79.
The tool pays the extra every month on top of the scheduled payment. It assumes a fixed rate and monthly payments, and it leaves out property tax, insurance and fees, so your lender’s statement may differ a little.
Check with your lender before you send extra money. Some loans charge a penalty for paying early, and some need you to say that the extra should go towards the principal.