Investment Growth Calculator
Project your investment portfolio growth with monthly contributions and a stacked area chart.
Project your investment portfolio growth with monthly contributions and a stacked area chart.
Lump sum you invest today.
Amount added each month.
Expected average annual return (e.g. 7–10% for equities).
Number of years to invest.
Compound growth means each year's gains also earn returns in subsequent years. Regular monthly contributions (dollar-cost averaging) smooth out market volatility and accelerate wealth accumulation, particularly over long time horizons.
Balance = P(1 + r/12)^(12t) + C × [(1 + r/12)^(12t) − 1] / (r/12)Investing $5,000 at age 25 at 8% annual return grows to over $108,000 by age 65. The same $5,000 invested at age 45 grows to only about $23,000 — less than a quarter as much. Time is the most powerful variable in compound growth.
Contributing $300/month with $0 initial investment at 8% over 30 years yields approximately $408,000 — with only $108,000 in actual contributions. The remaining $300,000+ is pure compound growth, illustrating the power of consistent investing.
Balance is calculated month-by-month: balance = balance × (1 + r/12) + monthlyContribution, where r = annualReturn/100. Yearly snapshots are captured. Total growth = finalBalance − totalContributions.