Calculate simple interest (SI = P �- R �- T ÷ 100) and the final maturity amount.
Simple Interest Calculator
The Simple Interest Calculator computes interest that is charged only on the original principal - the straightforward model used for many short-term loans and fixed deposits.
The simple interest formula
Simple interest uses I = P × R × T, where P is the principal, R is the annual rate (as a decimal), and T is the time in years. Unlike compound interest, it never charges interest on previously earned interest, so it grows in a straight line. On ₹10,000 at 8% for 3 years, the interest is 10,000 × 0.08 × 3 = ₹2,400.
When simple interest applies
It is common for short-term personal loans, some car loans, and certain deposits. Compare it with the Compound Interest Calculator to see how much difference compounding makes over longer periods - the gap widens dramatically with time.
Frequently Asked Questions
What is the difference between simple and compound interest?
Simple interest is charged only on the original principal; compound interest is charged on the principal plus previously accumulated interest, so it grows faster.
What is the simple interest formula?
Interest = Principal × Rate × Time, where the rate is annual (as a decimal) and time is in years.
When is simple interest used?
It is common for short-term loans, some auto loans, and certain fixed deposits where interest is not reinvested.
How do I find the total amount to repay?
Add the calculated interest to the original principal; the tool shows both the interest and the final total.
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