🌿 Free tool
Compound Interest Calculator
See how a little, saved consistently, snowballs over the years. Pick a rate, set your monthly habit, and watch compounding do the heavy lifting. 🌿
Enter your numbers to watch compounding work. 🌿
Track the real thing
The Ultimate Finance Dashboard tracks your savings & net worth — automatically.
A calm Google Sheet that charts your balances growing month over month, alongside budgets. From $24.
Questions
Good to know
How is compound interest calculated?
Your money earns returns, and then those returns earn returns too. This tool compounds monthly: each month your balance grows by the rate, then your contribution is added — repeated for every month of your timeline.
What rate should I use?
A high-yield savings account (HYSA) is around 4–5% today. The long-run stock market average is roughly 7% after inflation. Use a rate that matches where your money actually lives — and stay conservative for safety.
Is this a guarantee?
No — it's a projection, not a promise. Real returns vary year to year, especially for investments. It's a powerful way to see the shape of compounding, not a forecast of exact dollars.