Amortization Calculator
View your complete loan amortization schedule showing every payment broken into principal and interest.
Files processed in your browser — never uploaded to our serversWhat is Amortization Calculator?
An amortization calculator generates a complete payment-by-payment schedule for a fixed loan, showing exactly how much of each payment goes toward interest and how much reduces your principal balance. The key insight amortization tables reveal is front-loaded interest: in the early years of a mortgage, the vast majority of each payment is interest. On a $400,000 30-year mortgage at 7%, the first payment applies roughly $330 to principal and $2,333 to interest. By year 25, the ratio flips — most of each payment reduces principal. Understanding this schedule helps you see how extra payments build equity faster, where total interest accumulates, and when you cross the midpoint of repayment.
How to use
- Enter the loan amount, annual interest rate, and loan term in years.
- Optionally enter an extra monthly payment amount to see how it shortens the loan and reduces total interest.
- Click Calculate to generate the complete amortization schedule and summary totals.
- Review the summary: total interest paid, payoff date, and total loan cost.
- Examine the year-by-year table to see how the interest-to-principal ratio shifts over time.
- Experiment with extra payment amounts to find your ideal balance between payment size and long-term savings.
Why it matters
Most homeowners are surprised to discover how little principal their early payments reduce. In the first year of a 30-year mortgage at 7%, over 85% of each payment goes to interest. Extra payments made early have an outsized impact because they reduce the balance on which all future interest is calculated — the savings compound over the remaining loan life. Making one extra mortgage payment per year typically shortens a 30-year loan by 4–5 years and saves tens of thousands of dollars in interest. The amortization table makes this math concrete and helps you decide whether extra payments represent the best use of your money.
Pro tip
Confirm with your loan servicer how extra payments are applied. Some servicers apply extra funds to the next scheduled payment (saving only one month of interest), while others apply them directly to principal (reducing the balance and saving interest over the full remaining term). Always specify 'apply to principal' in writing when making extra payments — it is the default at some servicers but not all, and the difference in savings can be substantial.