Lump sum vs DCA
Invest the same money all at once or spread it out, over any historical period, and compare the results side by side.
Market data through Sep 2026, updated monthly. How we calculateComes out ahead in this period
Investing $12,000 at once in Jan 2020 grows to $30,824; spreading it over 12 months grows to $31,412. Across every 12-month spread since 1950, judged 10 years later, the lump sum won 76% of the time.
Spreading the money out keeps part of it in cash at 0% while it waits. S&P 500 monthly average prices, dividends reinvested (recent months use the last reported dividend, Jun 2023). Data through Sep 2026. One buy per month at that month's average price; no fees or taxes. Past returns do not predict future returns.
How this calculator works
One portfolio invests everything in the first month. The other invests an equal part each month over the spread, holding the rest in cash. Both are valued at the end date.
The win rate checks every starting month since 1950, judged 10 years later.
Common questions
Why does lump sum usually win?
Markets rise more often than they fall, so money invested sooner usually has more time to grow.
When does spreading out win?
When a fall comes soon after the start, as in early 2020 or 2008.
Which should I choose?
If investing everything at once would make you anxious enough to sell in a drop, spreading it over a few months is a reasonable trade.
FatDCA calculators are educational estimates, not investment, tax or legal advice. Results depend on the assumptions you enter, and past returns do not predict future returns.
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