About This Tool
The investment calculator estimates the future value of an investment when you make regular contributions over time. It's ideal for planning contributions to a 401(k), IRA, or taxable brokerage account. You can see how starting early, increasing contributions, or earning a higher return impacts your final balance. This tool helps you set realistic goals and stay motivated to invest consistently.
How It Works
It uses the future value of an annuity formula: FV = PV * (1+r)^t + PMT * [((1+r)^t - 1) / r], where PV is the initial investment, PMT is the periodic contribution (monthly or annual), r is the expected return per period, and t is the number of periods. The calculator assumes contributions are made at the end of each period. Results show the total balance and total contributions made.
Examples
- Investing $10,000 now and $500 per month for 30 years at 8% annual return yields about $758,000, with $190,000 in total contributions.
- Starting with $0 and investing $200 per month for 20 years at 6% return gives a future value of roughly $92,400.
Pro Tips
- Use a realistic return rate based on your asset allocation—7-9% for stocks, 3-5% for bonds, or a blended rate.
- Consider the impact of fees (expense ratios, advisory fees) by reducing your expected return by 0.5-1%.
- Increase your contribution amount annually (e.g., by 2-3%) to account for salary growth and inflation.