Compound Interest Calculator

Estimate how an initial balance and regular monthly deposits can grow over time under a steady annual return assumption.

Results

Future value:
$39,291.50
Total contributed:
$29,000.00
Estimated growth:
$10,291.50
Projection period:
10 years

How to interpret the projection

This estimate assumes a constant annual return converted to monthly compounding. Real results will vary, especially for investments where returns are uneven from year to year. Use the output to compare scenarios rather than to predict an exact balance.

  • Increasing time can have a bigger effect than increasing deposits slightly.
  • Early contributions compound for longer than later contributions.
  • Testing conservative and optimistic return assumptions can improve planning.

Yearly growth

YearProjected balance
1$7,711.58
2$10,561.89
3$13,558.03
4$16,707.45
5$20,018.01
6$23,497.94
7$27,155.91
8$31,001.03
9$35,042.87
10$39,291.50
Why does time matter so much?
Because returns can earn returns. The longer money stays invested or saved, the more periods of compounding it can experience.
Does this guarantee a future balance?
No. Savings accounts, CDs, and investments all behave differently. This is a planning estimate, not a guarantee.
Should I include taxes or fees?
If your real account has taxes, fund fees, or account charges, your actual ending balance may be lower than this simplified estimate.
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