Watch your money grow
See how a starting amount plus steady monthly contributions can snowball over time — thanks to the magic of compound interest.
Your plan
In 20 years
■ your contributions ■ compound growth
Where to grow it 🌿
Compare high-yield savings and investment accounts to put this to work.
The magic of compound interest
Albert Einstein reportedly called compound interest the eighth wonder of the world. The idea is simple: you earn returns not just on your original money, but on all the returns it has already earned. Given enough time, even modest monthly contributions can grow into a substantial sum — the earlier you start, the more dramatic the effect.
How to use this calculator
Enter a starting amount, how much you'll add each month, an estimated annual return, and a time horizon. A 7% average return is a common long-term stock-market assumption; a high-yield savings account might be 4%. Try lengthening the years to see how time supercharges growth.
Is 7% a realistic return?
Historically, a diversified stock portfolio has averaged roughly 7% per year after inflation over long periods — but returns vary year to year and are never guaranteed. Use a lower rate for savings accounts.
Does this account for taxes or inflation?
No — it's a simplified projection. Real results depend on taxes, fees, and inflation. Treat it as a motivational estimate, not a guarantee.