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Simple Interest Calculator

Calculate simple interest and the total amount on a principal.

Last updated: 8 Aug 2026

Quick answer

Simple interest is calculated as SI = P×R×T ÷ 100. For example, ₹1,00,000 at 10% for 5 years earns ₹50,000 interest, for a total of ₹1,50,000. Enter your principal, rate and time above to calculate instantly.

₹
% p.a.
years

Simple interest is calculated only on the original principal, using SI = P×R×T ÷ 100. It is common for short-term loans and some deposits. This calculator shows the interest and the total amount payable or receivable.

How to calculate simple interest

  1. 1 Enter the principal amount.
  2. 2 Enter the annual interest rate and the time in years.
  3. 3 We apply SI = P×R×T ÷ 100.
  4. 4 See the simple interest and total amount.

Frequently asked questions

What is the simple interest formula?
SI = P×R×T ÷ 100, where P is the principal, R the annual rate, and T the time in years. Total amount = P + SI.
When is simple interest used?
It is common for short-term loans, car loans in some cases, and certain fixed deposits, where interest does not compound.
How is it different from compound interest?
Simple interest is charged only on the principal, while compound interest also earns interest on accumulated interest.

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