Simple Interest Calculator

Simple Interest = Principal × Rate × Time / 100. Interest is calculated only on the original principal for the entire period — it does not compound.

Simple interest is charged only on the original principal throughout, while compound interest is charged on the principal plus any interest already accumulated — compound interest grows faster over the same rate and time. Use the Compound Interest Calculator to compare.

Some short-term loans, basic savings instruments, and certain bonds use simple interest, though most bank deposits and loans in practice use compound interest.

The interest amount earned or payable, and the total amount (principal plus interest) at the end of the time period.

Enter time in years for this calculator; convert months to a fraction of a year (e.g., 6 months = 0.5 years) if needed.