Simple Interest Calculator

Simple Interest Calculator: Calculate interest earned or owed using principal, rate and years.

Simple Interest Calculator

Simple Interest Calculator: Simple interest is calculated as principal × annual rate × years, without interest earning interest. The result adds that interest to the original principal.

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How to use Simple Interest Calculator

Simple interest is calculated as principal × annual rate × years, without interest earning interest. The result adds that interest to the original principal.

How Simple Interest Calculator calculates the result

Interest = principal × (annual rate ÷ 100) × years. Total amount = principal + interest. Interest is not added back to the principal between periods.

Example

1,000 at 5% simple interest for three years earns 150 interest, for a total of 1,150.

What to know

This model assumes a fixed annual rate and excludes fees, inflation, compounding and changes in principal.