Compound Interest Calculator
the 8th wonder of the world · see your money grow
> total_contributed$130,000.00
> interest_earned$327,014.25
> final_balance$457,014.25
> interest_ratio71.6% of total is interest
> growth_snapshot
> /reference
> Compound formula: A = P × (1 + r/n)^(n×t) + PMT × ((1 + r/n)^(n×t) − 1) / (r/n)
> P = initial principal · PMT = monthly contribution · r = annual rate · n = compounds/year · t = years
> S&P 500 historical average: ~10% nominal, ~7% real (inflation-adjusted)
> Rule of 72: divide 72 by your return % to estimate doubling time
> The power is time — doubling at 8%: year 0→10→20→30 = $10K→$22K→$47K→$101K
> NFA — past performance ≠ future returns. Invest wisely.