Compound Interest Calculator
Enter your starting balance, optional monthly contribution, annual rate, and years. Choose contribution timing to see the difference.
Contribution timing
Final amount
0.00 USD
Total contributions
0.00 USD
Interest earned
0.00 USD
FAQ
How do you calculate compound interest?
We apply compounding to the starting balance and add the future value of monthly contributions (ordinary or due).
What’s “start” vs “end” of period?
Start-of-period (annuity due) deposits earn one extra period of interest compared with end-of-period (ordinary) deposits.
Do results include taxes or fees?
No. This is an estimate and doesn’t include taxes, fees, or market fluctuations.