Compound Interest Calculator
Contribution timing
Final amount
$0.00
Total contributions
$0.00
Interest earned
$0.00
Principal
Contributions
Interest
About This Calculator
This calculator uses the standard compound interest formula, A = P(1 + r/n)nt, combined with the future value of an annuity for recurring deposits. You can choose between ordinary annuity (end-of-period) and annuity due (start-of-period) timing, which affects how much interest each deposit earns. It is useful for estimating growth on savings accounts, retirement funds, or any investment with a fixed rate. All results are estimates and do not account for taxes, inflation, or fees — consult a financial advisor for personalized guidance.
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.