Interest Rate Calculator
Estimate the annual interest rate on a loan when you know the loan amount, the monthly payment, and the loan term.
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About the Interest Rate Calculator
Sometimes you know what you'd borrow and what you can afford to pay monthly, but you want to back out the implied interest rate — for example, when comparing a 'no-rate-quoted' financing offer.
This calculator iterates Newton's method on the standard amortization formula to find the rate that makes the math balance.
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