NerdWallet Compound Interest Calculator – Free Tool 2025
🔒 Free · No sign-up · No data stored · Updated 2025
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Your Numbers

Initial Investment $10,000
$
Monthly Contribution $200
$
Annual Interest Rate 7%
0.1%5%10%15%20%
Time Period 20 years
1 yr10203550 yrs
Compounding Frequency
Reset to defaults
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Your results will appear here

Adjust the inputs on the left and click Calculate to see how your money grows over time.

Growth Over Time
Year-by-Year Breakdown
Year Balance Interest Earned Total Contributed
How to Get More From Compound Interest
1
Start as early as possible. Every decade you wait roughly halves your final balance. The math heavily rewards early starters.
2
Maximize your rate. Move savings from a 0.5% bank account to a 4.8% high-yield savings account today — it’s FDIC insured and free to open.
3
Automate monthly contributions. Set an auto-transfer on payday. Even $100/month at 7% for 30 years = over $117,000 in interest alone.
4
Never withdraw. Every dollar you pull out stops compounding permanently. The Rule of 72: at 7%, money doubles every ~10 years.

For informational purposes only — not financial advice.

Not affiliated with NerdWallet, Inc. · Results are estimates based on fixed assumed rates of return.