Calculator

Compound Interest Calculator

Calculate how your investments grow with compound interest. See final balance, total interest earned, and year-by-year growth.

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Compound Interest Calculator

See the power of compound interest. Calculate how your initial investment grows over time with regular contributions and compounding returns.

đŸ’ĩInvestment Details

Optional: additional amount added each month

đŸŽ¯Investment Results

Final Balance
$54,714
Total Interest Earned
$20,714
Total Contributions
$34,000
Contributions (62.1%)Interest (37.9%)
Formula used: A = P(1 + r/n)nt + PMT × [((1 + r/n)nt − 1) / (r/n)]
where P = principal, r = annual rate, n = compounds/year, t = years, PMT = periodic contribution

📊Year-by-Year Breakdown (First 10 Years)

YearBalanceTotal ContributionsTotal Interest
Year 1$13,201.42$12,400.00$801.42
Year 2$16,634.27$14,800.00$1,834.27
Year 3$20,315.28$17,200.00$3,115.28
Year 4$24,262.39$19,600.00$4,662.39
Year 5$28,494.83$22,000.00$6,494.83
Year 6$33,033.24$24,400.00$8,633.24
Year 7$37,899.74$26,800.00$11,099.74
Year 8$43,118.03$29,200.00$13,918.03
Year 9$48,713.55$31,600.00$17,113.55
Year 10$54,713.58$34,000.00$20,713.58

â„šī¸How Compound Interest Works

What is Compound Interest?

Compound interest is interest calculated on both the initial principal and the accumulated interest from previous periods. Unlike simple interest, compounding causes your money to grow exponentially — often called "the eighth wonder of the world."

How to Use This Calculator

  1. Enter your initial investment (principal)
  2. Set the annual interest rate (stock market avg ~7-10%)
  3. Choose how often interest compounds (more frequent = more growth)
  4. Enter the time period in years
  5. Optionally add a monthly contribution to supercharge growth

Typical Return Rates

S&P 500 (historical avg)
~10% per year
Bonds / Conservative
3–5% per year
High-Yield Savings
4–5% per year
Balanced Portfolio
6–8% per year

Disclaimer: Past performance does not guarantee future results. This calculator is for educational purposes only. Consult a financial advisor before making investment decisions.

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