Whether it’s a mortgage, car loan, or personal loan, the monthly payment formula involves an exponential term that’s genuinely painful to compute by hand — and seeing how much an extra payment each month actually saves in interest requires simulating the whole schedule, not just plugging into a formula once.
What Is the Mortgage / Loan Calculator?
Enter a loan principal, annual interest rate, and term in years, and get the standard amortized monthly payment, total interest paid over the life of the loan, and total cost. Optionally add an extra monthly payment amount to see the real payoff time and interest savings, plus a year-by-year amortization schedule.
How to Use It
- Open the tool at /tools/mortgage-calculator.
- Enter the loan amount, annual interest rate, and term in years.
- Optionally enter an extra monthly payment amount.
- Review the summary cards and the year-by-year schedule table below.
Key Features
- Standard fixed-rate amortization formula, the same math lenders use to calculate payments.
- Extra-payment simulation, showing the real shortened payoff time and reduced total interest, not just a static estimate.
- Year-by-year amortization schedule, breaking down principal paid, interest paid, and remaining balance per year.
- Works for any amortizing loan, not just mortgages — car loans and personal loans use the same formula.
When to Use This Tool
- Comparing loan offers with different rates or terms before signing.
- Modeling the effect of extra payments on your total interest and payoff timeline.
- Understanding how much of an early payment goes to interest vs. principal, via the yearly schedule.
Try It Now
Open Mortgage / Loan Calculator directly, or press ⌘K and type the tool name from anywhere on the site.
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