Investment Calculator
Project how your investments could grow over time with regular contributions.
Enter your numbers and select Calculate to see results.
About This Calculator
This calculator projects the future value of an investment portfolio, combining a starting balance with regular contributions at an expected annual rate of return. It's a general-purpose growth projection tool suitable for brokerage accounts, index funds, or any investment with an expected average annual return.
How This Is Calculated
A = P(1 + r/n)^(nt), with monthly contributions added at each compounding period
- P
- — Starting balance
- r
- — Expected annual return (decimal)
- n
- — Compounding periods per year (12, monthly)
- t
- — Time in years
$20,000 starting, $500/month, at 8% for 25 years grows to roughly $645,000.
Assumptions
- Assumes a fixed average annual return; real markets fluctuate significantly year to year.
- Does not account for taxes, fees, or inflation.
Frequently Asked Questions
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Last updated January 15, 2026. Results are estimates for informational purposes only — read our disclaimer.