Simple Interest Calculator

Calculate simple interest and the total amount payable or receivable on a principal amount over a given time period at a fixed annual interest rate.

  • Free to use
  • Accurate results
  • No registration required
  • Works on all devices
Enter the principal, annual interest rate, and time period to calculate simple interest using SI = P × R × T / 100, plus the total amount payable or receivable.
The initial amount of money (loan or deposit).
%
The annual simple interest rate.
The duration over which interest accrues, in years.

Your result

₹24,000

Simple interest

Total amount (principal + interest)₹1,24,000

AI explanation

Formula

SI = P × R × T / 100

Worked example

₹1,00,000 at 8% for 3 years

Worked example: ₹1,00,000 at 8% for 3 years
FieldValue
Principal amount100000
Interest rate (per annum)8
Time period (years)3
Simple interest24000
Total amount (principal + interest)124000

Assumptions

  • Interest is calculated only on the original principal — it does not compound.
  • Assumes a fixed annual interest rate for the entire time period.

Frequently asked questions

How is simple interest different from compound interest?

Simple interest is calculated only on the original principal for the full period. Compound interest is calculated on the principal plus any interest already accrued, so it grows faster over time. Use the Compound Interest Calculator to compare.

What kinds of loans or deposits use simple interest?

Some short-term loans, certain fixed-tenure deposits, and instruments like simple-interest bonds use this method. Most bank loans and deposits in India instead use compound (or reducing-balance) interest.

Can I use months instead of years for the time period?

Yes — convert months to years by dividing by 12 (e.g., 18 months = 1.5 years) before entering the time period.

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Sources

This calculator provides a mathematical estimate using the standard simple interest formula and is for general educational use. It does not represent an offer from any bank or financial institution.

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