Simple Interest Calculator
Find interest earned and total amount using the simple interest formula.
How to use
Simple interest does not compound — interest is calculated only on the original principal.
Formula
I = P × r × t · Total = P + I, where r is the annual rate as a decimal and t is time in years.
Frequently asked questions
When is simple interest used?
Short-term loans, some bonds, and basic savings products often use simple interest.
Do you store the numbers I enter?
Calculations run in your browser. Inputs are not sent to our servers.