Stock Dollar-Cost Averaging (DCA) Calculator
Project the future value of investing a fixed amount every month at an assumed annual return, with total invested and gain. Educational, not investment advice. Runs in your browser.
A long-run stock-market average is often assumed ~7% real / ~10% nominal.
Dollar-cost averaging invests a fixed amount on a schedule regardless of price. This projects the future value of those monthly contributions as an ordinary annuity: FV = PMT × ((1 + i)n − 1) ÷ i, where i is the monthly return and n the number of months. The assumed return is applied as a constant; real markets are volatile and returns vary year to year, so actual outcomes differ. Educational, not investment advice. Everything runs in your browser.
About this tool
Dollar-cost averaging (DCA) is the practice of investing a fixed amount of money at regular intervals — say $500 every month — regardless of the asset's price at the time. Because the same dollar amount buys more shares when prices are low and fewer when prices are high, DCA produces a lower average cost per share than the simple average of prices, and it removes the temptation (and the difficulty) of trying to time the market. It is the default strategy for most retirement and index-fund investors precisely because it is automatic, disciplined, and emotionally easier to stick with through downturns. This calculator projects what a stream of equal monthly contributions could grow to over time, treating the contributions as an ordinary annuity (invested at the end of each month) compounding at an assumed annual return: future value = monthly amount × ((1 + i)^n − 1) ÷ i, where i is the monthly return (annual ÷ 12) and n is the total number of months. It also separates the total you actually contributed from the investment gain, so you can see how much of the final balance is your own money versus growth. The key caveat is the assumed return: this model applies one constant rate, but real markets are volatile and returns arrive unevenly, so actual results will differ — sometimes substantially — from a smooth projection. A long-run US stock-market average often cited is roughly 10% nominal (about 7% after inflation), but the past does not guarantee the future. This is educational and explicitly not investment advice. Everything runs in your browser; nothing is uploaded.
How to use it
- Enter the fixed amount you plan to invest each month.
- Enter the number of years you will keep contributing.
- Enter an assumed annual return (e.g. 7% real or 10% nominal for broad stock indices).
- Read the projected final value, the total you contributed, and the investment gain.
Frequently asked questions
- What is dollar-cost averaging?
- Investing a fixed dollar amount at regular intervals regardless of price. It buys more shares when prices are low and fewer when high, lowering your average cost per share and removing the need to time the market.
- How is the future value of DCA calculated?
- As an ordinary annuity: FV = monthly amount × ((1 + i)^n − 1) ÷ i, where i is the monthly return (annual rate ÷ 12) and n is the number of months. This calculator also shows total contributions and the gain on top.
- What return assumption should I use?
- For broad stock indices, a long-run average of roughly 10% nominal or about 7% after inflation is often cited. These are historical averages, not guarantees — real returns vary year to year and the future may differ.
- Is DCA better than investing a lump sum?
- Historically, investing a lump sum immediately has often outperformed DCA on average because markets tend to rise over time. But DCA reduces the risk of investing everything just before a drop and is easier to do with regular income. Compare both with the lump-sum vs DCA tool.
- Why is my projection different from reality?
- This model applies one constant return every month. Real markets are volatile and returns are uneven, so actual outcomes differ — the projection is an illustration of compounding, not a forecast.
- Is this investment advice?
- No. It is an educational projection. Markets carry risk and returns are not guaranteed. Nothing is uploaded; all math runs in your browser.