Simple Interest Calculator
Calculate simple interest and final amount from principal, rate and time.
Results are provided for general informational use. Verify important financial, health or legal figures before relying on them.
About this Simple Interest Calculator
The Simple Interest Calculator uses the basic P × R × T formula, where interest is calculated only on the original principal. Unlike compound interest, previously earned interest does not become part of the interest-bearing balance.
For related tasks, try Compound Interest Calculator, Loan EMI Calculator or Investment Return Calculator.
How to use it
- Enter the original principal.
- Enter the annual rate and time in years.
- Calculate to view interest and principal plus interest.
Practical example
For a principal of 10,000 at 6% per year for three years, simple interest is 1,800 and the final amount is 11,800.
Frequently asked questions
What is the simple interest formula?
Interest = principal × annual rate × time, with the rate expressed as a decimal.
Does interest compound?
No. Simple interest is based on the original principal only.
Can I use fractional years?
Yes. Decimal year values such as 1.5 are accepted.
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