Compound interest calculator
See how your money grows over time and with contributions.
How it works
Set your initial capital
And, if you want, a monthly contribution.
Enter rate and years
The annual interest rate and the term.
See the growth
Final balance, contributed and interest, with a chart.
The power of compound interest
Compound interest is, as many investors say, the eighth wonder of the world: interest generates more interest. The earlier you start and the longer you let the money grow, the bigger the effect. This calculator shows the difference between what you put in (initial capital plus contributions) and what the interest adds up to.
Try changing the term and the monthly contribution to see how time is your biggest ally. Remember it's a simulation with a constant interest rate; the real return of an investment varies and is not guaranteed.
Frequently asked questions
Quick answers to the most common questions about this tool.
What is compound interest?
Can I add regular contributions?
Is the interest annual or monthly?
Are the results guaranteed?
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