Compound Interest Calculator
Grow a starting balance with regular contributions and compounding returns.
Method
How it works
The annual rate is divided by the selected compounding frequency. Monthly contributions are converted into an equivalent contribution for each compounding period, then both the starting balance and contributions grow through the full term.
The calculator separates money invested from interest earned. When the annual return is zero, it simply adds the starting amount and every contribution without applying growth.
Common questions
Frequently asked questions
When are contributions assumed to be made?
They are treated as equal contributions added once per compounding period after converting the monthly amount to that frequency.
What happens if the return is zero?
The future value becomes the starting amount plus all regular contributions.
Are taxes and account fees included?
No. Reduce the annual return or adjust the inputs if you want to model those effects.
Not financial advice. This calculator is for general informational purposes only. Check figures independently before making financial decisions.