Compound interest means you earn interest on your interest, so time matters as much as the amount you save. Enter a starting amount, a monthly deposit and an expected annual return, and see the balance after the period you choose, how much of it is your own money and how much is growth, and a comparison across different periods.
How to use
- Enter the starting amount and the monthly deposit.
- Enter the expected annual return and the number of years.
- Read the final balance and compare the growth over different periods.
Why this tool is safe
This page loads no tracking scripts, and its security policy forbids it from sending data to other servers. The work happens in your browser's memory and is gone when you close the tab.
Frequently asked questions
How is compound interest calculated here?
Interest is compounded monthly at the annual rate รท 12, and each monthly deposit is added at the end of the month. This matches how most savings plans and investment funds are reported.
What annual return should I use?
Use the rate your savings account offers, or a conservative estimate for investments. Returns on investments are not guaranteed and can be negative in some years.
Does it account for fees, tax or inflation?
No. Management fees and tax reduce the real return, and inflation reduces what the money will buy. To approximate them, lower the annual return accordingly (for example 6% return โ 1% fees = 5%).