Calculators

Simple Interest Calculator

Interest on principal, rate & time.

Interest
Total amount

▸ Interest per period
PeriodInterestBalance

This free simple interest calculator uses the classic formulaI = P × R × T to find the interest on a principal amount at a fixed annual rate over a period of time, plus the total repayable. It is ideal for short-term loans and quick estimates. All maths runs in your browser.

Related tools