How to use the Mortgage Amortization Calculator
This tool shows how a mortgage balance falls year by year and how much of each year's payments goes to interest and principal.
Open the Mortgage Amortization Calculator →
What you need to enter
- Loan amount ($)
- Interest rate (% / year)
- Loan term (years)
The formula
Monthly payment = P × r ÷ (1 − (1 + r)^−n). Each month interest = balance × r, and the rest of the payment reduces the balance.
Worked example
Using the default values in the calculator:
- Loan amount ($): 350000
- Interest rate (% / year): 6.25
- Loan term (years): 30
| Monthly payment | $2,155.01 |
| Total of payments | $775,803.67 |
| Total interest | $425,803.67 |
Tips for better results
- Compare the first and last years to see how the interest share changes.
- Use it with the mortgage payoff calculator to test extra payments.
Common mistakes to avoid
- Reading the yearly table as if payments were yearly.
- Ignoring that an adjustable rate changes the schedule.
Please note: Calculators and guides give general estimates, not financial, tax or investment advice. Real offers depend on your lender, location and personal situation. See our Disclaimer.