Compound Interest Calculator
See how an initial amount plus monthly contributions grows over time with compound interest.
Total invested
$13,000.00
Interest earned
$5,150.63
Final balance
$18,150.63
Yearly evolution
| Month | Invested | Balance |
|---|---|---|
| 12 | $3,400.00 | $3,663.33 |
| 24 | $5,800.00 | $6,664.43 |
| 36 | $8,200.00 | $10,046.14 |
| 48 | $10,600.00 | $13,856.75 |
| 60 | $13,000.00 | $18,150.63 |
What is compound interest?
Compound interest means the interest earned in one period is added to the balance and starts earning interest itself in the next period. Combined with regular contributions, small amounts can grow substantially over time.
Calculated instantly, on your device
The simulation runs month by month directly in your browser as you type — there is no server call.
Frequently asked questions
How is an annual rate converted to monthly?
We use the compound conversion formula so that twelve consecutive monthly periods match the informed annual rate exactly.
Does this account for inflation or taxes?
No, the result is a gross nominal projection. Real returns after inflation and taxes will be lower.
What if I don't make monthly contributions?
Set the monthly contribution to zero to see the growth of a single lump sum over time.
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