Compound Interest Calculator
See how investments grow with compounding and monthly contributions.
Project the future value of an investment with compound interest and optional monthly contributions. Choose annual, monthly, daily or continuous compounding and see a year-by-year balance breakdown.
Common use cases
- Project retirement savings growth over decades
- Compare daily vs monthly compounding for high-yield savings accounts
- See the impact of adding a monthly contribution
- Demonstrate the power of compounding for financial education
Frequently asked questions
What's continuous compounding?▾
The mathematical limit as compounding frequency approaches infinity, computed via A = Pe^(rt).
How are contributions handled?▾
Monthly contributions are added at each compounding period — exact for monthly compounding, approximated for other frequencies.
Is interest taxed in the projection?▾
No — this is pre-tax growth. Subtract your effective tax rate for after-tax estimates.