How to use the DCA calculator
- Enter the fixed amount you intend to invest each month.
- Select how many years the contributions could continue.
- Enter a hypothetical annual return and compare several scenarios.
- Review projected value, cash invested and modeled growth.
Dollar-cost averaging, or DCA, means investing equal amounts at regular intervals regardless of market movements. The SEC’s Investor.gov definition notes that a fixed amount buys more units when prices are lower and fewer when prices are higher. That discipline does not guarantee a profit.
How the DCA projection is calculated
This calculator treats each contribution as occurring at the beginning of the month, followed by that month’s modeled return. Mathematically, that is an annuity-due calculation.
Beginning-of-month DCA formula
FV = C(1 + i) × [((1 + i)^n − 1) ÷ i]
FV is projected value, C is the monthly contribution, i = annual return ÷ 12, and n = years × 12. Total invested equals C × n, and projected growth equals FV − total invested. With a zero return, future value is simply C × n.
Projection value versus actual DCA cost basis
The calculator uses a smooth constant-return model. It cannot calculate the actual number of shares purchased because it does not receive a monthly price history. With real purchase prices, total shares equal Σ(C ÷ price at purchase), while average cost per share equals total invested divided by total shares.
This distinction matters: the displayed result is a future-value scenario, not a historical backtest or a promise about average purchase price.
Assumptions and limitations
The projection assumes identical beginning-of-month contributions, monthly compounding and one unchanged annual return. Every contribution is invested immediately and no withdrawals occur.
Fees, bid-ask spreads, taxes, inflation, missed contributions and time spent uninvested are excluded. Dividends are included only if the entered rate represents total return with distributions reinvested. Actual returns vary, and their sequence changes real outcomes.
DCA can support discipline, but it does not ensure a lower cost or positive return. If you already hold a lump sum, gradual investing leaves part of it in cash. FINRA’s discussion of DCA benefits and limitations explains that potential opportunity cost and the effect of repeated transaction fees.
Worked DCA examples
These use hypothetical constant returns and beginning-of-month investments.
$250 monthly for five years
At 4%, $15,000 is invested over 60 months. The projected value is approximately $16,630, including roughly $1,630 of modeled growth.
$500 monthly for 15 years
At 6%, contributions total $90,000 and the projected balance is about $146,136. Projected growth accounts for roughly $56,136.
$1,000 monthly for 25 years
At 8%, invested cash totals $300,000. The constant-return model projects approximately $957,367; reality could be materially higher or lower.
Connect DCA to a broader plan
A contribution should remain affordable during both rising and falling markets. Test a lower-return case and avoid assuming that a volatile investment will follow a smooth path. A larger contribution increases cash invested, but it does not protect against losses.
Use the compound interest calculator with an initial balance, or compare the recurring plan with a retirement target in the FIRE calculator.
Common questions
DCA Calculator FAQs
What is the difference between DCA and lump-sum investing?
DCA divides purchases across a schedule, while lump-sum investing puts available cash to work at once. DCA reduces dependence on one entry date, but holding uninvested cash may create opportunity cost.
Does dollar-cost averaging guarantee a profit?
No. Regular purchases do not prevent an asset from losing value. The result still depends on investment performance, fees, taxes, diversification and the withdrawal date.
How often should I make DCA investments?
Monthly or payday-aligned contributions are common, but the suitable interval depends on cash flow and transaction costs. Consistency matters more to this projection than a particular calendar date.
Does DCA always lower the average purchase price?
No. Equal contributions buy more units at lower prices and fewer at higher prices, but the resulting average is not guaranteed to beat an earlier lump-sum purchase.
What annual return should I use in a DCA calculator?
Treat the rate as a scenario. Compare lower, middle and higher assumptions appropriate to the investment, and account for expenses rather than treating historical performance as guaranteed.
Does this calculator include dividends, fees or taxes?
Not separately. Reinvested dividends may be represented by a total-return input, but fees and taxes must be modeled independently or approximated by reducing the return.
Can I use DCA for individual stocks or cryptocurrency?
A fixed purchase schedule can be applied to many assets, but it does not remove concentration, liquidity or volatility risk. The chosen asset still determines the investment risk.
Why will my real DCA balance differ from this projection?
Real prices move unevenly, while this calculator applies a constant monthly rate. Return sequence, timing, fees, taxes, distributions and skipped deposits can all change the result.