Simple Interest Calculator

Calculate simple interest earned or owed on a principal amount.

Updated April 2026 · CalcFlow Editorial

$
%
Enter values above and click Calculate to see your results.

How to Use

  1. Enter the principal amount.
  2. Enter the annual interest rate.
  3. Enter the number of years.
  4. Click Calculate.

Formula

Interest = Principal x Rate x Time (I = PRT)

Frequently Asked Questions