Investment Return Calculator
Project the value of an investment using a steady estimated annual return.
How this is calculated
Ending value = initial × (1 + r)^n + monthly × [((1 + r)^n − 1) ÷ r], where r is the monthly rate (annual rate ÷ 12) and n is the number of months (years × 12). The first term compounds the starting balance; the second adds up each monthly deposit with the interest it earns from the month it is made. At a 0% rate the second term simplifies to monthly × n.
How to use this estimate
Enter a planning assumption, not a promise. The model compounds monthly and adds deposits at the end of each month. Real investments fluctuate, and fees, taxes, inflation, withdrawals, and changing contributions can materially alter the outcome.
Worked example
An initial $5,000 with $250 added monthly at an estimated 7% annual return, compounded monthly, over 15 years (180 months) gives an ending value of about $91,000. Of that, $50,000 came from deposits ($5,000 plus 180 × $250) and about $41,000 from estimated growth.
FAQ
- What return should I enter?
- Use a range of conservative, expected, and optimistic scenarios rather than one number. Diversification and time horizon affect risk, and past performance does not guarantee future returns.
- Does this include investment fees?
- No. To approximate a fee drag, reduce the annual return assumption by the expected annual fee, while remembering that fees may be charged differently.