Dollar-Cost Averaging Simulator

Two ways to deploy the same amount of money

If you have a lump sum to invest — a bonus, an inheritance, savings you’ve been sitting on — you have two basic choices: invest it all at once, or spread it out over months and buy in gradually. Dollar-cost averaging (DCA) is the second approach. It doesn’t change how much you’re investing, only when each portion actually hits the market.

Key terms

Dollar-cost averaging (DCA)

Investing a fixed total amount in equal installments over a set period, rather than all at once — buying more shares when the price is low and fewer when it’s high, without trying to time the market.

Lump sum

Investing the entire amount immediately, in a single transaction. The comparison point for DCA in this calculator.

DCA interval

How often each installment is invested — weekly, monthly, or another fixed cadence. This calculator uses a 24-month window; shorter or longer windows change how much the outcome can diverge from a lump sum.

Average cost basis

The average price per share you actually paid across all your DCA purchases. Because you buy more shares when prices are low, your average cost basis under DCA is often lower than the price at any single point in time.

Why DCA isn’t a return-boosting strategy

DCA is often discussed as if it were a way to improve returns, but that’s not really what it does. In a market that trends upward over your investing window — which markets do, on average, over long periods — investing a lump sum immediately means more of your money is exposed to that upward trend for longer. Statistically, lump-sum investing outperforms DCA more often than not, precisely because markets rise more often than they fall. The “Steady Growth” scenario above demonstrates this directly.

What DCA actually does: reduce regret risk

DCA’s real value isn’t a return advantage — it’s psychological and risk-management insurance against a specific bad outcome: investing everything right before a downturn. Run the “Crash and Recover” scenario above and compare it to lump sum; DCA can come out ahead specifically because spreading purchases across the decline means buying more shares at the cheaper prices along the way, lowering your average cost basis compared to buying everything at the peak.

Why the scenario you pick changes the answer entirely

There’s no universally correct answer between these two strategies — the “right” choice depends entirely on what the market actually does after you invest, which nobody can know in advance. Toggle through all four scenarios above and notice how the winner flips depending on the pattern. That’s the actual lesson: DCA is a hedge against uncertainty, not a strategy that reliably beats lump-sum investing.

A middle path worth knowing about

Many investors split the difference — DCA-ing a lump sum over a shorter window, like 3 to 6 months instead of leaving it in cash for years, to get most of the growth exposure of a lump sum while limiting the single-worst-case scenario of investing everything the day before a sharp drop. This calculator uses a 24-month window to make the mechanism clear, but shorter DCA windows are common in practice.

Using this calculator

These four price paths are deliberately simplified, hand-built illustrations — not historical data for any real asset, and not a prediction. Use them to understand the mechanism, not to pick a specific investment strategy based on which scenario “wins.” Real markets don’t move in clean patterns like these, and past performance of any real asset doesn’t predict its future.

Example

Investing $24,000 across the "Crash and Recover" scenario above: a lump sum invested all at once ends the period worth $27,120.00. Spreading the same $24,000 evenly across all 24 months instead ends worth $30,213.60 — DCA comes out $3,093.60 ahead here, purely because it bought more shares while the price was down before the recovery.

Switch to the "Steady Growth" scenario with the same $24,000, though, and the result flips: lump sum ends at $32,400.00 versus DCA's $27,905.42 — lump sum wins by $4,494.58, because none of the month-over-month dips DCA is designed to soften ever showed up.

This article is for educational purposes only and isn't legal, financial, or tax advice. See our Disclaimer for details.

Frequently asked questions

Does DCA beat lump sum investing?

Not on average. Because markets rise more often than they fall over long periods, investing a lump sum immediately outperforms dollar-cost averaging more often than not. DCA's value isn't a return edge — it's protection against the specific bad luck of investing everything right before a downturn, as the calculator's scenarios above demonstrate directly.

How often should I dollar-cost average?

There's no single correct interval — monthly is common because it matches how most people get paid. Spreading a lump sum over a shorter window (a few months) captures most of the growth exposure of investing immediately while still softening the single worst-case scenario; spreading it over a much longer window trades away more growth exposure for more downside protection.

Is DCA good for a 401(k)?

Every regular 401(k) contribution from a paycheck is already a form of dollar-cost averaging, since you're investing fixed amounts on a fixed schedule rather than in one lump sum. The DCA-versus-lump-sum question mainly comes up when you have a windfall or lump sum to deploy outside of that regular paycheck cadence.

What's the psychological benefit of DCA?

It removes the pressure of picking a single moment to invest a large sum, which is a decision that causes real hesitation and can lead to money sitting in cash far longer than intended while waiting for a 'better' time. Committing to a fixed schedule up front takes market timing out of the decision entirely.