Interest Rate Calculator
Find the interest rate on a loan when you know the amount, the monthly payment and the number of months.
How the interest rate calculator works
A loan payment depends on three things: the amount, the rate and the term. If you know the amount, the payment and the term, the rate is the one number left. The calculator tests rates until the payment on the loan matches yours.
The formula it solves
Example: A $20,000 loan paid back at $400 a month for 60 months has an annual rate of about 7.42%. You pay $24,000.00 in total, which includes $4,000.00 of interest.
The rate shown is the nominal annual rate (monthly rate x 12). Fees that are not in the monthly payment are not included, so use the APR calculator if the loan has upfront fees.
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Frequently asked questions
How do I find the interest rate on a loan?
Use the loan amount, monthly payment and number of months. This calculator solves the payment formula for the rate.
Is this the same as APR?
It is the nominal annual rate. APR also includes fees, so the APR can be higher on loans with upfront costs.
Why does it say payments must add up to more than the loan?
If your payments total less than the amount borrowed, the loan would have a negative rate, which this tool does not calculate.
How does the term change the rate?
For the same payment, a longer term means you pay off a smaller balance each month, so the calculation gives a different rate.
Can I use this for a car loan or personal loan?
Yes, for any fixed-rate loan with equal monthly payments.
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