Simple interest calculator

Simple interest = principal × rate × time. For example, 10,000 at 5% a year for 3 years earns 1,500 in interest, giving a total amount of 11,500. Time can be entered in years, months or days.

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%

Please enter the rate stated in your agreement or product terms. This tool does not suggest a rate.

years
Time in

Result

Please complete the details. The result will appear here.

How it is calculated

  1. Simple interest = principal × annual rate × time in years (SI = P × R × T ÷ 100, where R is the rate in per cent).
  2. For time in months, years = months ÷ 12. For time in days, years = days ÷ 365.
  3. Total amount = principal + simple interest.
  4. Interest if compounded yearly = principal × ((1 + annual rate)^years − 1), with interest added to the principal once a year.
  5. Amounts are shown to two decimal places.
  6. All calculations are done in your browser. The details you enter are not sent to any server.

Worked examples

10,000 at 5% a year for 3 years

Details
Principal ₹10,000.00; rate 5% a year; time 3 years
Result
Interest ₹1,500.00; total amount ₹11,500.00

50,000 at 8% a year for 9 months

Details
Principal ₹50,000.00; rate 8% a year; time 9 months
Result
Interest ₹3,000.00; total amount ₹53,000.00

20,000 at 6% a year for 120 days

Details
Principal ₹20,000.00; rate 6% a year; time 120 days
Result
Interest ₹394.52; total amount ₹20,394.52

25,000 at 7.5% a year for 4 years

Details
Principal ₹25,000.00; rate 7.5% a year; time 4 years
Result
Interest ₹7,500.00; total amount ₹32,500.00