Dollar-Cost Averaging Calculator
Dollar-cost averaging (DCA) is the practice of investing a fixed dollar amount at regular intervals, regardless of market conditions. Rather than trying to time the market with a single lump-sum purchase, DCA spreads your investment over time, automatically buying more shares when prices are low and fewer when prices are high. This calculator uses the future value of an annuity formula to project the growth of your periodic investments over your chosen time horizon. Enter your contribution amount, investment frequency, expected annual return, and the number of years you plan to invest. The results show your total contributions, total growth, and ending portfolio value - giving you a clear picture of how consistent investing compounds into significant wealth over time. DCA is particularly well-suited to 401(k) plans and other payroll-deduction savings programs.
Dollar-cost averaging formula
FV = Initial x (1 + r)^n + PMT x (((1 + r)^n - 1) / r)
Where r = annual rate / frequency, n = years x frequency
PMT is your periodic contribution, r is the periodic interest rate, and n is the total number of periods. The initial lump sum compounds separately at (1 + r)^n.
How DCA reduces timing risk
- When prices fall, your fixed contribution buys more shares, lowering your average cost.
- When prices rise, you buy fewer shares, but your existing holdings gain value.
- Over many periods, your average purchase price tends to be lower than the average price over that period.
- DCA enforces discipline by automating contributions, removing emotion from investment decisions.
- 401(k) payroll deductions are the most common real-world application of DCA.
Dollar-cost averaging: frequently asked questions
What is dollar-cost averaging?
Dollar-cost averaging (DCA) is an investment strategy where you invest a fixed dollar amount at regular intervals regardless of the asset price. When prices are low you buy more shares; when prices are high you buy fewer. Over time this averages out your cost per share and reduces the impact of market volatility.
Does DCA outperform lump-sum investing?
Academic research, including studies by Vanguard, shows that lump-sum investing outperforms DCA about two-thirds of the time because markets tend to rise over long periods. However, DCA reduces regret risk and is practical for investors who receive income periodically rather than having a large lump sum available.
How is the DCA future value calculated?
The future value of a series of equal periodic payments is calculated using the future value of an annuity formula: FV = PMT x (((1 + r)^n - 1) / r), where PMT is the periodic payment, r is the periodic interest rate, and n is the number of periods.
What annual return should I use?
The S&P 500 has historically returned roughly 10% per year before inflation and about 7% after inflation. For conservative planning use 6-7%; for moderate use 8%; for optimistic use 10%. These are illustrative and not guaranteed.
Does the calculator account for taxes and fees?
No. This calculator shows the pre-tax, pre-fee growth. In practice, fund expense ratios, brokerage commissions, and taxes on dividends or capital gains will reduce your actual return. Use the net-of-fees return to get a more realistic estimate.
Official sources
- U.S. Securities and Exchange Commission (SEC): Dollar Cost Averaging.
- IRS: 401(k) Contribution Limits.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.