Simple Interest Calculator
Calculate interest charged on the principal only, with no compounding.
Your result will appear here as soon as you add some input.
How to use it
- 1Enter your values in the fields above.
- 2The answer and the working appear immediately below.
- 3Check the working to see the formula with your numbers substituted.
Formulas used
- I = P x R x T / 100
About the Simple Interest Calculator
Simple interest is charged on the original principal for the whole term, so it grows in a straight line rather than a curve.
Very few real products work this way. Some short-term loans and certain bond coupons do; savings accounts and mortgages compound. Comparing a "flat rate" against a compounding rate without converting first always flatters the flat rate.
Questions people ask
Is your figures uploaded to a server?
No. This tool runs entirely in your browser using standard web APIs, so your figures never leaves your device. You can confirm it by opening your browser's network panel while the tool runs, or by disconnecting from the internet after the page has loaded.
Is it free, and do I need an account?
Yes, it is free, and there is no account, no sign-up and no watermark on the result. The project is funded by optional donations.