Compound Interest Calculator
Project investment growth over time with regular contributions and custom compounding frequency.
Future value$144,573
Total interest earned$86,573
Total principal$10,000
Total contributions$58,000
About the Compound Interest Calculator
This calculator projects how an investment grows when interest compounds on itself over time. Enter a starting principal, an optional monthly contribution, an annual interest rate, and how often interest compounds, and the tool simulates your balance month by month across the full investment term. It's most useful for comparing how contributing a bit more each month, choosing a different compounding frequency, or extending your time horizon would change your final balance — the earlier you start, the more time compounding has to work in your favor.