DCA Calculator

Year-by-year breakdown

The same projection as the chart, in numbers. The lump-sum column assumes your entire eventual total was invested on day one at the same return.

What dollar-cost averaging is

Dollar-cost averaging (DCA) means investing a fixed amount of money on a fixed schedule, such as $200 every month into an index fund or $50 every Friday into Bitcoin, regardless of what the price is doing. When the price is low your fixed amount buys more units; when it is high, fewer. Over time your average cost per unit smooths out, and you do not have to decide whether now is a good time to buy.

The term gets used for two quite different situations, and it pays to know which one you are in:

• Investing income as it arrives. You invest part of every paycheque because that is when the money exists. The term is used for this too, and there is no alternative to compare it against: you cannot lump-sum money you have not earned yet.
• Spreading an existing lump sum. You have $50,000 from a bonus, a sale or an inheritance, and you drip it in over months instead of investing it today. This is the situation the research below measured.

How the calculator works

The model converts your annual return to a per-period rate, then steps through every scheduled buy:

Each contribution starts compounding the moment it is invested, so 10% a year is exactly 10% a year whether you buy weekly or monthly. The lump-sum line answers a specific question: if the whole total you will eventually invest had gone in on day one, at the same return, where would it be? At any positive return that number is higher than the DCA line in a smooth model, because later dollars compound for less time. It is not the comparison the research below measures: those studies compared a sum already in hand, paid in over 3 to 12 months, with the same sum invested at once, using historical market returns.

What the research says about a lump sum and instalments

These studies do not measure investing from each paycheque. They compare two ways of investing a sum that is already in hand: all at once, or in equal monthly instalments while the rest waits in cash. Vanguard’s authors make the same distinction between the two meanings of the term and say their analysis is about a lump sum that is available immediately.

• Vanguard Research, Finlay and Zorn, February 2023, also summarized in Vanguard UK’s article of 4 January 2026. Markets and periods: rolling one-year periods in index data from 1976 to 2022: United States (Russell 3000, from 1979), United Kingdom (FTSE All-Share, from 1986), Canada (S&P/TSX Composite, from 1985), Europe (MSCI Europe, from 1998), Australia (S&P/ASX 300, from 1992), emerging markets (MSCI Emerging Markets, from 1988) and global (MSCI World, from 1976 in US dollars and pounds, from 1998 in euros). What was compared: a lump sum invested at once against equal monthly instalments over 3, 4, 5 or 6 months, with the two compared one year after the start. What it found: the lump sum finished ahead in 61.6% (emerging markets, 3 instalments) to 73.7% (United States, 6 instalments) of periods. With a 3-month split, median wealth after one year was 2.2% higher for the lump sum with 100% equities, 1.8% with 60% equities and 40% bonds, and 1.2% with 40% equities and 60% bonds (MSCI World and the Bloomberg U.S. Aggregate Bond Index, 1976 to 2022).
• PWL Capital, Benjamin Felix, June 2020. Markets and periods: rolling 10-year periods in six stock markets, in US dollars, with monthly returns to March 2020: Australia (MSCI Australia), Canada (S&P/TSX Composite), Germany (MSCI Germany), Japan (MSCI Japan), the United Kingdom (MSCI United Kingdom) and the United States (CRSP 1-10, from 1926). What was compared: a lump sum against 12 equal monthly instalments, the waiting cash earning the one-month US Treasury bill rate and both portfolios fully in stocks once invested, with ending assets compared after 10 years. What it found: the lump sum had the higher ending assets in 64.89% of periods on average across the six markets (57.53% in Japan to 70.59% in the United States; 64.89% is the average the paper prints, and the six market figures it lists average 64.87%). Over all periods, wins and losses together, the lump sum’s annualized 10-year return was 0.38% higher on average (0.32% in Australia to 0.41% in the United States).

The two studies cannot be added together: they use different markets, holding periods (one year and 10 years), numbers of instalments and portfolios. Neither studied a plan of monthly buys over several years, and neither studied crypto.

Both papers trace the result to the cash that waits. Vanguard reports that over 1976 to 2022 US stocks beat cash, measured by the 3-month Treasury bill rate, 76% of the time, and US bonds beat it 68% of the time. PWL’s model pays the waiting cash the one-month Treasury bill rate. Vanguard’s global example (MSCI World, 100% equities, 3 instalments, compared after one year) pays it nothing and has the lump sum ahead 68% of the time; with the 3-month Treasury bill rate paid on the cash, the paper reports 65% for an all-equity portfolio. With 12 equal monthly instalments and the first on day one, as in this calculator, an average of 45.8% of the sum is not yet invested over the year, counting the cash left after each month’s instalment: the same as the whole sum sitting in cash for 5.5 of the 12 months.

What the studies say about the cases people worry about

An average hides the outcomes that make people hesitate, and the studies report those too.

• Vanguard, the worst and best cases. With a 3-month split and wealth compared after one year (MSCI World and a US bond index, 1976 to 2022), the 5th percentile of ending wealth was higher with cost averaging, by 3.6% with 100% equities, 1.4% with 60% equities and 40% bonds, and 0.6% with 40% equities and 60% bonds. At the 95th percentile it was higher with the lump sum, by 6.4%, 4.6% and 3.7%.
• Vanguard, instalments against staying in cash. In its global example (MSCI World, 100% equities, 3 instalments, compared after one year, cash measured by the 3-month Treasury bill rate) cost averaging finished ahead of leaving the whole sum in cash 69% of the time.
• Vanguard, who its model says prefers instalments. The authors modelled three investor profiles that differ in how much they dislike risk, with and without a penalty for losses. In its model with a penalty for losses (set at 2.50), the moderately conservative and very conservative profiles preferred cost averaging and the adventurous profile preferred the lump sum. With no penalty for losses, only the very conservative profile preferred cost averaging. The paper’s explanation is that cost averaging lowers a portfolio’s risk for a time, which can limit the drawdown, and the regret that comes with it, in a severe downturn; it also finds that the longer the instalments run, the greater the opportunity cost.
• PWL, after a 20% fall. For starts in the month after a monthly drop of 20% or more from the previous peak, the lump sum had the higher ending assets in 53.66% of cases on average (33.33% in the United Kingdom to 78.57% in Canada), and its annualized 10-year return was 0.25% higher on average.
• PWL, the psychological side. The paper says that, despite the statistics, investing a lump sum carries a psychological risk: buying and then watching the price fall is more painful than not buying and watching it rise, even when the money at stake is the same, and instalments can be seen as spreading that decision over time.

DCA for crypto: same arithmetic, larger swings

The calculator treats crypto like any other asset: you type a constant annual return and it shows the result. For Bitcoin, iShares’ article (11 July 2024, updated 28 July 2025) says bitcoin averaged a 54% annualized return from 2014 to 2024, was the best-performing asset in its comparison in eight of those 11 years and the worst in the other three. The table in the same article, with data to 30 June 2025, shows an annualized 74% for 2015 to mid-2025, so the figure depends on the window chosen. It also reports four drawdowns of more than 50% since 2014, the three largest between 77% and 83% (about 80% on average), and says that in three of the four major corrections the price took nearly three years to recover.

• Scheduled purchases are a product feature. As one example, Crypto.com’s help centre describes a Recurring Buy that automates crypto purchases on a set schedule, with a minimum purchase of US$1, and says the total amount received is the purchase amount minus any applicable fees. Other exchanges and brokers have their own terms, which this page did not check.
• Fixed fees weigh more on small purchases. A fee of a fixed amount per purchase is a larger share of a smaller purchase: $1 on a $10 weekly buy is 10% of that purchase before the price moves at all. This calculator ignores fees.
• DCA changes the purchase dates, not the asset. It smooths the average price paid; it does not change what the asset does between purchases. The lump-sum studies above used stock and bond indexes, so they say nothing about whether a lump sum or instalments would have done better in Bitcoin.

Worked example 1 — the index-fund saver

Sana invests a $1,000 starting lump sum plus $500 a month into an S&P 500 index fund for 15 years, assuming the long-run 10% nominal return.

• Total contributed: $91,000 ($1,000 up front + 180 × $500).
• Final value: about $204,988 — total growth of roughly $113,988, more than her own contributions.
• Day-one lump sum comparison: if the whole $91,000 had been invested on day one, it would grow to about $380,130 — $175,142 more. But Sana never had $91,000 on day one; she had a salary. For her, monthly investing is the lump-sum strategy: every dollar went in as soon as it existed.

Worked example 2 — the BTC accumulator

Danish sets a $50 weekly recurring Bitcoin purchase, no starting balance, for 5 years. He models an arbitrary 20% a year, well below the 54% average iShares reports for 2014 to 2024.

• Total contributed: $13,000 (260 weekly buys).
• Final value: about $21,261 — roughly $8,261 of growth.
• Day-one lump sum comparison: $13,000 invested at once would reach about $32,348. In real Bitcoin history the gap between the two paths depends on the start date: iShares’ table lists a 77% drawdown that began on 10 November 2021 and took 849 days to reach market recovery. The smooth model has no down years, so it cannot show a path like that.

Reading the result

• The schedule changes only when the money goes in. The model buys at the start of each period, so at the same annual total a monthly plan has its money invested slightly earlier on average than a weekly one (see the FAQ).
• The day-one comparison is about a sum you hold. If the plan is income invested as it arrives, there is no day-one sum, and the gap shown is only the arithmetic of later dollars compounding for less time.
• The result depends on the return entered. The presets are scenarios, not forecasts: 10% for the S&P 500 with dividends (it compounded at 10.0% a year over 1928 to 2025, before inflation), 7% as a round-number lower case, and 54% for Bitcoin (iShares' figure for 2014 to 2024; its table shows 74% for 2015 to mid-2025).

Everything on this page is general information and math, not financial advice. Markets can fall for years; crypto can fall further and faster. Talk to a licensed adviser about your own situation.

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