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SIMPLE INTEREST GUIDE

How to use the simple interest formula

Simple interest is based only on the original principal. It does not add earlier interest to the balance for future periods.

FORMULA

simple interest = principal × annual rate × time ÷ 100

WORKED EXAMPLE

For principal 1,000 at 5% per year for 3 years: 1,000 × 5 × 3 ÷ 100 = 150 interest. Total amount is 1,150.

STEP BY STEP

01

Enter the principal

The principal is the original amount borrowed or invested before interest is added.

02

Use annual rate and time

Enter the annual percentage rate and the number of years. Convert months to part of a year when necessary.

03

Add interest to principal

The final amount equals original principal plus the simple interest result.