# Simple Interest Calculator

getcalc.com's **Simple Interest (SI) Calculator** is an online finance tool to calculate the interest return on the principal amount lent at certain rate of interest for a particular period of time.

## Definition & Formula

**Simple Interest** is a finance function or method used in the context of time value of money calculation, often abbreviated as SI, represents the interest return for the principal amount on a certain percentage of interest rate for a specific period of time. In simple interest calculation, the principal amount never change, during the interest accumulation period.