Transparent method
The formula
Worked example
Example inputs
How to interpret the result
Dollar-cost averaging spreads risk across time, while historically, investing a lump sum immediately has outperformed spreading it out more often than not, simply because markets rise more years than they fall. The two approaches trade expected return against the emotional comfort of not deploying everything at once right before a downturn.
Before you rely on it
What to check
Decide explicitly whether the goal is maximizing expected return or reducing the regret of bad timing, since the two strategies serve those two different goals differently.
The common error
Where people go wrong with DCA vs. lump sum calculator
Assuming dollar-cost averaging is the mathematically superior strategy because it feels more cautious. Across most historical periods, investing available cash immediately has produced a higher expected outcome, even though it carries more short-term timing risk.
Sensitivity evidence
How expected annual return changes the modeled lump-sum advantage
| Expected annual return | Modeled lump-sum advantage | Lump-sum ending value | DCA ending value |
|---|---|---|---|
| 5.0% | $1,733 | $77,002 | $75,268 |
| 6.0% | $2,178 | $80,931 | $78,753 |
| 7.0%worked example | $2,661 | $85,058 | $82,396 |
| 8.0% | $3,185 | $89,391 | $86,206 |
| 9.0% | $3,752 | $93,941 | $90,189 |
Every input, tested
Which input moves the modeled lump-sum advantage most
| Input | Tested from | To | Modeled lump-sum advantage at each end | Swing |
|---|---|---|---|---|
| Months used to invest gradually | 9.0 months | 15.0 months | $1,947 to $3,368 | $1,421 (53%) |
| Expected annual return | 6.0% | 8.0% | $2,178 to $3,185 | $1,007 (38%) |
| Total cash available | $54,000 | $66,000 | $2,395 to $2,927 | $532 (20%) |
| Investment horizon | 4.0 years | 6.0 years | $2,482 to $2,854 | $372 (14%) |
Two variables at once
Modeled lump-sum advantage by expected annual return and total cash available
| Expected annual return \ Total cash available | $48,000 | $60,000 | $72,000 |
|---|---|---|---|
| 5.0% | $1,387 | $1,733 | $2,080 |
| 6.0% | $1,743 | $2,178 | $2,614 |
| 7.0% | $2,129 | $2,661 | $3,194 |
| 8.0% | $2,548 | $3,185 | $3,822 |
| 9.0% | $3,002 | $3,752 | $4,503 |
Step by step
The worked example, input by input
| Input | Value used |
|---|---|
| Total cash available | $60,000 |
| Expected annual return | 7.0% |
| Investment horizon | 5.0 years |
| Months used to invest gradually | 12.0 months |
| Modeled lump-sum advantage | $2,661 |
| Lump-sum ending value | $85,058 |
| DCA ending value | $82,396 |
Where the inputs come from
Total cash available is the sum you could invest, expected annual return is your assumption for the investment, the horizon is how long you will hold it, and months used to invest gradually is how long you would spread the purchases. While cash waits to be invested it is assumed to earn nothing here, which is the cautious case. Use a realistic return for the fund you would buy.
Using the modeled lump-sum advantage in a real decision
Spreading purchases helps only by lowering the chance of investing just before a fall, and it buys peace of mind more than return.
When the result stops applying
The model assumes a steady return, so it cannot show the case where prices fall right after a lump-sum purchase, when dividing the money would have helped. Real markets are lumpy. If the money would otherwise sit in a savings account paying interest, the gap narrows. Fees per transaction can add cost when you make many small purchases.
What to compare it with
Run the dollar-cost averaging calculator for regular contributions from income, which is a different situation because you do not have the lump sum. Check the maximum drawdown page to see how much a loss right after investing could hurt, and decide whether you could stay invested through it.
People also ask
Frequently asked questions
Which is better, dollar-cost averaging or lump sum?
Lump sum has historically come out ahead about two-thirds of the time because markets tend to rise, but averaging reduces regret if prices fall soon after.
How long should I spread out the investment?
Six to twelve months is common. Longer periods keep more cash idle and give up more expected return.
Does this apply to my paycheck contributions?
No. Investing from each paycheck is dollar-cost averaging by necessity, since the money arrives over time, and the lump-sum comparison does not apply.