Simple Interest Calculator

Calculate simple interest on a loan or deposit, and see how it compares with annual compounding.

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How to use the Simple Interest Calculator

Enter the principal amount.
Enter the annual rate of interest.
Enter the time and choose years, months or days.

Formula used

SI = P × R × T ÷ 100

Amount = P + SI

P = principal, R = annual rate in %, T = time in years (months ÷ 12, days ÷ 365).

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Simple Interest Calculator — FAQs

What is the simple interest formula?▾

SI = P × R × T ÷ 100, where P is principal, R the yearly rate in percent and T the time in years.

Where is simple interest used?▾

Short-term loans, some personal and car loans, delayed-payment interest on invoices, and many informal loans use simple interest.

Simple vs compound interest?▾

Simple interest is charged only on the principal. Compound interest is also charged on accumulated interest, so it grows faster over time.

How do I calculate interest for days?▾

Divide the number of days by 365 and use that as T. Interest on ₹1 lakh at 10% for 90 days is 1,00,000 × 10 × 90/365 ÷ 100 = ₹2,466.

How to use the Simple Interest Calculator

Formula used

Simple Interest Calculator — FAQs

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