Compound Interest Calculator
Project savings growth with compounding and regular contributions, and see the year-by-year balance.
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
- A = P x (1 + r/n)^(n x t)
About the Compound Interest Calculator
Compounding means interest earns interest. The effect is small in the first years and dominant in the last - which is why the year-by-year table is more useful than the final figure alone.
Frequency matters less than people expect. At 7%, moving from annual to monthly compounding adds about 0.23 percentage points a year; moving from monthly to daily adds almost nothing. The rate and the term do the work.
Regular contributions are treated as arriving at the end of each compounding period, which is the conservative convention. Real returns also vary year to year, so treat any projection as an illustration rather than a forecast.
Questions people ask
Is this investment advice?
No. It is arithmetic on the numbers you enter, with a fixed assumed rate. Real investments fluctuate, and this cannot account for fees, tax or inflation. For decisions about your money, speak to a licensed adviser.
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.