Compound Interest Calculator
Calculate compound interest and investment growth over time. Supports monthly contributions, different compounding frequencies, and yearly breakdown.
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Final Balance
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Total Invested
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Interest Earned
Invested: —
Growth: —
Frequently asked
questions
Compound interest is interest calculated on both the initial principal and the accumulated interest from previous periods. This creates exponential growth — often called "the eighth wonder of the world."
Compounding can happen daily, monthly, quarterly, or annually. More frequent compounding means slightly more interest earned. Most savings accounts compound daily or monthly.
A = P(1 + r/n)^(nt), where A is the final amount, P is principal, r is annual interest rate (decimal), n is compounding frequency per year, and t is time in years.