📈 Finance
Compound Interest Calculator
📈
Compound Interest Calculator
See exactly how your money grows over time
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Initial investment$0
Total contributions$0
Total deposits$0
Total interest earned$0
Return (ROI)0%
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Interest
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Final Balance
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Balance growth year by year
Principal + Contributions
Interest Earned
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What is Compound Interest?
Compound interest is the process of earning interest on both your initial investment (principal) and on the interest you've already earned. Unlike simple interest, compound interest grows exponentially over time — making it one of the most powerful forces in personal finance.
The Compound Interest Formula
A = P(1 + r/n)^(nt) — Where A is the final amount, P is the principal, r is the annual interest rate (decimal), n is compounding frequency per year, and t is time in years.
Why Monthly Contributions Matter
Adding regular monthly deposits dramatically accelerates wealth building. Even $100/month added to a modest initial investment can massively increase your final balance over 10-20 years thanks to compound interest working on each new deposit.