Compound Interest Calculator
Find out how much your money can grow over time. Enter the initial amount, monthly contribution, interest rate and period — and watch the compounding snowball effect on an interactive chart, with a month-by-month breakdown.
📊 Dados do investimento
How compound interest works
Compound interest is "interest on interest": each period, the return is calculated on the accumulated balance (principal + previous interest), not only on the initial amount. The formula is M = C × (1 + i)ⁿ.
That is why time is the investor's greatest ally — the earlier you start, the bigger the exponential effect.
Time and consistency win
Regular monthly contributions, even small ones, make a huge difference. Reinvesting returns instead of withdrawing them is what makes wealth grow exponentially.
Frequently asked questions
Is the rate monthly or yearly?
The main field uses the monthly rate. The equivalent yearly rate is shown automatically below it.
Is anything saved on a server?
No. Everything is calculated in your browser in real time. Nothing is uploaded.
Does it work for any fixed-income product?
Yes. Use the estimated net monthly rate of the investment to simulate any product with contributions.