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Simple Interest Calculator

I = P × R × T — calculate, solve, schedule

Calculate Simple Interest

I = P × R × T ÷ 100
Initial amount
Per year
Duration
Total Interest
Final Amount
Monthly Interest

Solve for Unknown Variable

I = P × R × T ÷ 100

Enter any three values to solve for the fourth.

Enter 3 of 4 values

About Simple Interest

Simple interest is calculated only on the original principal, not on accumulated interest. The formula is I = P × R × T ÷ 100 where P is the principal, R is the annual rate in percent, and T is time in years.

Unlike compound interest, simple interest grows linearly. It's commonly used for short-term loans, car loans, and some bonds.