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Investing · calculator
Compound interest
How money grows when interest earns interest.
After 20 years
$124,379
- You put in
- $53,000
- Growth
- $71,379
That is a very high rate — real returns this high rarely last.
Fix the highlighted number to see the result.
Your balanceWhat you put in
Interest earns interest: each month the return is added to the balance, and next month’s return is worked out on the bigger number. That is why the last years add the most.
This calculator adds interest monthly and your top-up at the end of each month — the same maths the games use.
An example return, not a prediction: real returns go up and down, and high rates rarely last.
Education, not financial advice.
Feel it in a game
Rocket Growth turns this into a few quick rounds — in the app, and soon in your browser.