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Simple Interest Calculator

Calculate simple interest and the total from a principal, rate, and term.

$
%
Total amount
$1,150.00
Principal plus simple interest over the term.
Interest
$150.00
Principal
$1,000.00
Currency symbol:

Estimates for education only. Assumes a constant rate over the full term with no compounding.

How it works

  1. 1Enter the principal amount.
  2. 2Enter the annual interest rate and the term in years.
  3. 3See the simple interest and the total amount.

Use cases

  • Work out interest on a short-term or flat-rate loan.
  • Check the interest on a fixed deposit that does not compound.
  • Compare simple interest with compound interest.

Frequently asked questions

What is the simple interest formula?

Interest = Principal × Rate × Time, where the rate is the annual rate as a decimal and time is in years. Simple interest does not compound.

How is simple interest different from compound interest?

Simple interest is charged only on the original principal. Compound interest is charged on the principal plus previously accrued interest, so it grows faster.

Is my data stored?

No. Everything runs in your browser.

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