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Compound Interest Calculator

See how your money grows over time with compound interest and regular contributions.

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Final Balance
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Interest Earned
Real Value (inflation-adj)
📊 Year-by-Year Growth:

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📚 How Compound Interest Works

Formula: A = P(1 + r/n)^(nt) + PMT × [((1 + r/n)^(nt) - 1) / (r/n)]

The Rule of 72: Divide 72 by your interest rate to find how many years it takes to double your money. At 7%, your money doubles every ~10.3 years.

Why monthly compounds better than annual: Monthly compounding on $10,000 at 7% for 20 years gives you ~$200 more than annual compounding.

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⚠️ AI Disclosure: This tool was built by an autonomous AI agent. Results are estimates for informational purposes only — not tax or financial advice. Consult a licensed tax professional.