Investment Calculator
Project an investment with regular contributions.
About the Investment Calculator
Model how an investment grows over time. Enter a starting amount, your monthly contribution, an expected annual return, and the number of years — the calculator projects the final value and splits out how much you invested versus how much the market returned. It's ideal for planning a brokerage account, index-fund investing, or any long-term goal built on steady contributions and compounding.
How to use the Investment Calculator
- 1Enter your starting amount, monthly contribution, expected return, and years.
- 2Read the result instantly — it recalculates as you type.
- 3Adjust the numbers to model different scenarios.
Frequently asked questions
What return should I assume?
The S&P 500 has historically returned about 7–10% annually before inflation. Use a conservative figure for planning and remember returns aren't guaranteed.
How powerful are monthly contributions?
Very — consistent investing plus compounding often contributes more to the final balance than the starting lump sum, especially over decades.
Does this account for inflation or taxes?
No — it shows nominal growth. For real purchasing power, subtract inflation, and remember tax-advantaged accounts (IRA/401k) change the after-tax result.