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simple interest calculator online tool showing principal rate time interest and total

Simple Interest Calculator

Calculate simple interest on a principal amount over a set period.

Simple interest

SI = P × R × T / 100. Time can be a fraction of a year (for example 0.5). Not the same as compound interest.

How to Use the Simple Interest Calculator in 5 Steps

  1. 1

    Enter the principal amount.

    Add the starting balance.

  2. 2

    Enter the interest rate.

    Specify the supported annual rate.

  3. 3

    Enter the time period.

    Add the supported duration.

  4. 4

    Run the calculator.

    Process the inputs with the tool.

  5. 5

    Review the interest and total amount.

    Confirm the output fits your task.