About this compound interest calculator
Compound interest is interest that earns interest: each period, the interest you have already earned is added to your balance, so the next period's interest is calculated on a larger amount. Over years, that snowball effect makes a big difference. This calculator lets you enter a starting amount, a yearly interest rate, how long you save for, and an optional regular monthly deposit, then choose how often interest is added (yearly, quarterly, monthly or daily). It shows three numbers: the future value of your savings, the total you put in, and the interest earned on top. The figures are estimates that ignore tax and fees, and everything is calculated in your browser.
Frequently asked questions
- What is compound interest?
- It is interest calculated on your original money plus the interest already added, so your balance grows faster over time than with simple interest.
- Does "interest added" change the result?
- Yes, a little. Adding interest more often — daily rather than yearly — produces slightly more growth for the same rate.
- Are tax and fees included?
- No. The result is a clean estimate before any tax, charges or inflation, which vary by person and place.