Simple Interest Calculator

Use this simple interest calculator to find returns on your investment or loan amount by providing principle, interest rate and tenure. The SI calculator is easy to use and needs only few inputs to calculate simple interest.

Simple Interest Calculator

What is Simple Interest (SI)?

Simple interest is a method of calculating the interest on a loan or an investment. It is based on a fixed percentage of the original amount, known as the principal, and does not take into account any additional factors such as compounding.

SI Full Form: Simple Interest

The formula for calculating simple interest is:

Interest = (Principal * Rate * Time) / 100


  • Principal is the initial amount of money involved.
  • Rate is the annual interest rate (expressed as a percentage).
  • Time is the time period for which the interest is calculated, usually in years.

The resulting value represents the amount of interest earned on an investment or the amount of interest paid on a loan over the specified time period.

For example, if you invest Rs. 1 Lakh at a simple interest rate of 5% per year for 3 years:

Interest = (1,00,000 * 5 * 3) / 100 Interest = (5,000 * 3) Interest = Rs. 15,000

In this scenario, the simple interest earned over 3 years would be Rs. 15,000.

It’s important to note that simple interest does not take into account the effect of compounding, where the interest itself earns interest over time. Simple interest is commonly used for short-term loans, simple investment schemes, and certain types of financial calculations where compounding is not a factor.

What is Simple Interest Calculator?

Scripbox’s simple interest calculator will help you to quickly calculate the interest earned on an investment or paid on a loan using the simple interest formula. You provide the principal amount, the interest rate, and the time period, and the calculator gives you the total interest amount.

You will find Scripbox’s simple interest calculators free to use online. Here’s how you can use the SI calculator:

  • Input the Principal: Enter the initial amount of money you’re investing or borrowing. This is called the principal amount.
  • Input the Interest Rate: Enter the annual interest rate as a percentage. For example, if the interest rate is 5%, you would enter 5.
  • Input the Time Period: Enter the time for which the interest is being calculated, usually in years.
  • Calculate: Click the “Calculate” button, and the calculator will apply the simple interest formula to provide you with the total interest earned or paid.