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Everyday tool
Simple Interest Calculator
Use the simple interest formula for quick rough borrowing or saving checks.
Instant useNo sign up, quick result.
Clear outputMade for fast practical checks.
Related next stepsJump to supporting tools after.
Use the simple interest calculator
Calculate simple interest from principal, rate and time.
Result: waiting for input
Enter your values to see the result.
Formula
Simple interest = principal × rate × time
Example
£1,000 at 5% for 3 years creates £150 of simple interest.
Frequently asked questions
How is this different from compound interest?
Simple interest does not earn interest on past interest.
When is this useful?
It is good for quick estimates and basic comparisons.
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