Fastway Tools

Simple Interest Calculator

Interest$150.00
Total amount$1,150.00

The Simple Interest Calculator works out the interest and the total amount from a principal, an annual rate and a time period, using the classic I = P × r × t formula.

How to Use the Calculator

  1. Enter the principal amount.
  2. Set the annual interest rate and the time in years or months.
  3. Read the interest and the total amount.

Benefits and Use Cases

  • Check the interest on a short-term loan or deposit.
  • Compare simple versus compound interest for the same inputs.
  • Runs entirely in your browser — your figures stay private.

FAQ

How is simple interest calculated?

Simple interest is principal × rate × time. Unlike compound interest, it is charged only on the original principal.

When is simple interest used?

Some short-term loans, bonds and savings products use it. For long-term growth, compound interest applies instead.

Is my data saved?

No. The calculation runs entirely in your browser and nothing is uploaded.