← Blogby Marcell Almeida

How to calculate monthly loan payments

Any fixed-rate installment loan — enter principal, APR, and term in months to see payment and total interest.

Personal loans, auto loans, and equipment financing all use the same math: fixed monthly payments over a set term. The Loan Calculator gives you the payment and total interest in one screen.

Try it — enter amount, rate, and term in months

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How it works

  1. Loan amount — total principal.
  2. Annual interest rate — APR from your lender.
  3. Term in months — e.g. 36 for 3 years, 60 for 5 years.

Months vs years

This calculator takes term in months, not years. A 5-year loan = 60 months. For mortgages measured in years, use the Mortgage Calculator.

Zero-interest loans

If the rate is 0%, payment is simply principal ÷ months. The calculator handles this automatically.

The How to calculate monthly loan payments is free, runs locally, and never sends your data to a server. More finance calculators at maratool.com.