Compound Interest Calculator
Watch compounding multiply your money
Compound interest means you earn returns on both your original principal and accumulated interest. Use this calculator to see the effect over years.
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Projected Balance Over Time
Contributions vs. Growth
Final Breakdown
Assumptions: Compounding and contribution timing follow your selections above (defaults: annual compounding, end-of-period contributions). Optional deposits are included when provided.
Projections are estimates only and not guaranteed returns or financial advice.
How This Calculator Works
Your balance grows at the compounding frequency you choose, and any additions are applied at the start or end of each period. Results show ending balance, total contributed, and interest earned.
Example
$5,000 at 7% for 15 years with no additions grows to about $14,000 (annual compounding). Adding $200/month dramatically increases the outcome.
FAQ
How often does interest compound here?
You choose annually or monthly. Annual compounding is the default; monthly is a common approximation for many investment accounts.
What if my rate changes?
Recalculate with a different rate. Real returns vary year to year.