Enter values and select Calculate to see your result.
Find the implied annual interest rate from loan payments
Solves a fully amortizing fixed-rate loan with monthly payments, excluding fees. The result is a nominal annual rate, not a fee-inclusive APR.
How to use the Interest Rate Calculator
Find the implied nominal annual rate for a fully amortizing loan from balance, payment and term.
- Enter original principal, monthly payment and monthly payments.
- Check that the payment can amortize the balance.
- Calculate the implied nominal annual rate.
Interest Rate Calculator formula
The solved rate makes the present value of the payment stream equal the principal.
Worked example
Inputs: $10,000 principal, $200 monthly payment and 60 payments.
What to expect: The tool returns the nominal annual rate implied by those cash flows, excluding fees.
How to read your result
This is not APR when fees are charged; an insufficient payment may produce no valid positive rate.
Frequently asked questions
Does this return APR?
No. It returns nominal annual rate and excludes fees.
Why is no rate found?
The principal, payment and term may not describe a valid fully amortizing loan.