FREE CALCULATOR
Interest Rate Calculator
Find a simple annual interest rate from principal, interest earned and time.
Simple annual rate5.000%
Total amount$11500.00
This uses a simple-interest relationship. Compound-interest products require a different calculation.
CALCULATOR GUIDE
About the Interest Rate Calculator
Estimate an implied interest rate from principal, interest and time inputs for simple-interest scenarios.
How to use this calculator
- Enter the values requested by the calculator and check their units.
- Choose assumptions that match the scenario you want to estimate.
- Review the result and change one input at a time to compare scenarios.
- Verify important decisions against the relevant agreement, institution or official guidance.
How the calculation works
For simple interest, interest equals principal × rate × time; solve for rate when the other values are known.
Example
If $1,000 earns $50 simple interest over one year, the implied annual simple rate is 5%.
Things to keep in mind
- Confirm whether your scenario uses simple interest, compounding or regular loan payments.
- Fees and amortizing payments can make the effective rate different.
- The result is an estimate based on the inputs and assumptions provided.
- Check applicable terms and official guidance before making financial, employment or academic decisions.
Frequently asked questions
Is this the same as APR?
Not necessarily. APR may include certain fees and uses product-specific rules.
Are results guaranteed or official?
No. The tool provides an estimate or arithmetic result and may not include every real-world rule, fee or policy.
Can I compare scenarios?
Yes. Change one input at a time to see how it affects the result.