Interest Rate Calculator

Home › Financial Calculators › Interest Rate Calculator

Find the interest rate on a loan from the loan amount, monthly payment and term.

Table of Contents

How the calculation works

The payment formula cannot be solved directly for the rate, so the calculator searches for the rate that makes the monthly payment match yours.

Find r such that Payment = P × r ÷ (1 − (1 + r)^−n)

A $20,000 loan repaid at $400 a month over 5 years has an interest rate of about 7.42% a year.

Is this the APR?

It is the annual rate implied by the payment. Fees are not included.

Why is my result an error?

If the payments add up to less than the loan amount, no rate can match them.

Results are estimates for general information only and are not professional financial, medical or legal advice.

Every calculator on the site, in four categories.

💰

🥗

📐

🧰