Simple Interest Calculator
Interest on a principal amount without compounding.
Result
How to use
- 1
Enter the principal, rate and time.
- 2
See the simple interest and total amount instantly.
Questions
What is the simple interest formula?
SI = P × R × T ÷ 100, where P is the principal, R the yearly rate in % and T the time in years.
Where is simple interest used?
Some personal loans between people, certain short-term loans and many textbook problems use simple interest. Bank deposits usually use compound interest.
About this Simple Interest tool
Simple Interest Calculator — Interest on a principal amount without compounding. It is one of 200 free tools on namasivayam.in, made by software engineer Namasivayam Vadivelan for everyday use in India.
Everything is calculated instantly in your browser: nothing you type or upload is sent to any server, there is no sign-up, and it works on mobile and desktop. Enter the principal, rate and time.
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Results are estimates to help you plan. They are not financial, tax or medical advice.