Simple interest
Calculate interest on a fixed principal.
Inputs
Use the units shown—
Enter your values and select Calculate.
Formula & explanation
I = P × r × t ÷ 100
Variables & units
- Principal
- Numeric value · minimum 0
- Annual rate
- % · minimum 0
- Time
- years · minimum 0
Worked example
10,000 at 5% for 2 years earns 1,000.
Assumptions
The result is interest only; it excludes the principal.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
Use the default input values to find the answer. The reset icon restores those values.
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