Simple Interest Calculator
Simple interest is charged only on the original amount. Enter the principal, the yearly rate and the time.
Principal, Rate & Time
Calculate simple interest — interest charged only on the original principal — plus the final balance and the interest earned per year.
Formula
interest = principal × rate ÷ 100 × time (years). Final balance = principal + interest.
Reference Values
- •Used for short-term loans and bonds
- •Grows linearly, unlike compound interest
- •Fractional years are supported
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FAQ
Common questions about Simple Interest Calculator
How we calculate this
We use the standard published formula for this calculation, and we show the working so you can check it.
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Financial disclaimer
Results are estimates based on the numbers you enter. Real products have fees, rate changes and rules this tool does not model. Check figures with your lender or a qualified adviser before you decide.