Compound Interest Calculator
See how your money snowballs — with an initial deposit, monthly contributions and compounding. Includes a year-by-year growth chart and full breakdown of contributions vs. interest.
🔒 100% private. Calculations run in your browser. Your numbers never leave your device.
Savings details
Projected balance
$0
Total contributions
$0
Interest earned
$0
Year-by-year growth
| Year | Contributions | Interest | Balance |
|---|
How compound interest works
FV = P(1 + i)ⁿ + PMT × [ ((1 + i)ⁿ − 1) / i ]
where P is the initial deposit, PMT the regular contribution, i the interest rate per compounding period, and n the number of periods. Interest earns interest — which is why the curve bends upward over time.
The chart and table simulate month by month: contributions are added monthly, and interest is credited at your chosen compounding frequency.
Note: A 7% return is a common long-run stock market average before inflation — actual returns vary and can be negative in some years. This tool assumes a constant rate for illustration. Not financial advice.
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