Compound Interest

This calculator shows how compound growth works over time when you combine an initial portfolio, consistent monthly contributions, and an assumed annual rate of return.

Starting portfolio
Monthly contribution
Time horizon (years)
Annual return rate (%)
Starting portfolio
$25,000
Contributions
$120,000
Interest earned
$1,237,456
Ending value
$1,382,456
Total Contributions
Total Interest Earned
Year-by-Year Breakdown
Detailed annual view showing how contributions and growth affect your portfolio each year. Values below are annual, not cumulative.
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