Loan Payment Calculator
Estimate the fixed monthly payment, total repayment, and total interest for a principal-and-interest amortizing loan.
Estimate a fixed monthly loan payment
How this tool works
This calculator estimates a level monthly principal-and-interest payment for a conventional amortizing loan. It also totals the scheduled payments and subtracts the original principal to expose the estimated interest cost over the selected term.
For monthly rate r and n payments, payment equals P times r times (1+r)^n divided by ((1+r)^n minus 1). At a zero rate, payment is P divided by n.
How to use it
- Enter the amount borrowed as the principal.
- Enter the nominal annual interest rate and term in years.
- Review the monthly payment, total scheduled payments, and estimated interest.
Worked examples
Fifteen-year loan
- Input
- 100,000 principal, 7% annual rate, 15 years
- Output
- Approximately 898.83 monthly
The monthly rate is the annual rate divided by 12, and the term contains 180 payments. Applying the amortization formula gives the fixed estimate.
Zero-interest loan
- Input
- 12,000 principal, 0% rate, 2 years
- Output
- 500 monthly
With no interest, the special zero-rate case divides the principal evenly across 24 monthly payments, avoiding division by zero in the standard formula.
Limitations
- The estimate excludes fees, insurance, taxes, penalties, and rate changes.
- It is an educational estimate and not lending or financial advice.