Updates automatically as you type.
Calculated in your browser; your inputs are not sent to us. Privacy
Calculation details
Planning estimate only, not financial, tax, or legal advice. Verify assumptions and current rules before making decisions.
This tool runs in your browser. Your calculator inputs and results are never transmitted to us or to ad/affiliate partners. Ads and sponsored links may set third-party cookies to serve and measure them, but they never receive your calculation values. If you explicitly save a scenario, its permitted fields stay in local browser storage until you clear them. See our Privacy Policy.
Use this result
Share the current inputs or ask ChatGPT to explain the calculation in context.
More options
What does this calculator estimate?
DCA calculator: dollar cost average your investments and see total shares, average cost basis, and returns across recurring buys. Free, runs in browser.
A schedule is not a forecast
Dollar cost averaging fixes two things: a dollar amount and a frequency. The calculator prices what that schedule produces under a return assumption you supply. When it reports that $250 a month for 10 years at 7% compounds to about $45,281, the sentence is conditional, and the condition is the 7%. Change it to 5% and the same money ends near $38,818; change it to 9% and it ends higher. The tool is reporting the consequence of the assumption, which is a useful thing to know and a different thing from a prediction.
This distinction matters most at the moment of deciding what to contribute. If the plan feels too timid, the inputs that actually change the outcome are the monthly amount and the years, not the rate, because the rate is not under your control. Bumping the contribution from $250 to $300 adds $6,000 of principal over the schedule and lets compounding work on all of it. No amount of optimism typed into the rate field does that. Set the rate from a long historical average you are comfortable with, then make the decision with the numbers that are actually yours.
Why the early contributions carry the growth
Every dollar in the schedule does not work equally long. The first $250 compounds for nearly the full 10 years; the final $250 works for about half a month before the clock stops. At a 7% annual assumption, a dollar contributed in year 1 has roughly a factor of 1.07 to the 9th, about 1.84, applied to it by the end, while a dollar contributed in the final year grows by a factor near 1.03. The same dollars are not worth the same to the ending value depending on when they arrive.
That asymmetry has a practical edge: being 25 years old instead of 35 matters more than being clever about which fund, under any fixed return assumption, because the extra decade multiplies every contribution's compounding window. It also explains a common disappointment. Two people contributing identical amounts for 10 and 20 years do not end 2x apart; the longer run ends far higher because its principal had twice as long and growth compounds on growth. If a shorter schedule than you wanted is all you can afford, the honest response is a larger contribution, not a larger rate assumption.
Lump sum versus the same money spread over twelve buys
Suppose $12,000 arrives at once. Option one invests all $12,000 immediately. Option two holds it and buys $1,000 each month for a year. Under a steadily positive return assumption, option one ends higher, plain arithmetic: money invested on day one earns from day one, while the staggered version keeps roughly half its dollars idle through the year. The calculator can show both pages of that comparison by running once with $12,000 initial and zero contributions, then again with zero initial and $1,000 contributions, no additional rate change needed.
The spread schedule exists anyway, and legitimately, because nobody knows the near-term path of the market right after they receive money. Averaging in through a falling stretch buys more shares with the same dollars, which is the benefit people are describing. That is a risk-management preference about when you enter, not a higher expected return; under the calculator's smooth assumptions the immediate version simply wins. Say the actual trade to yourself: the spread schedule may cost some ending value relative to the best case, and it buys protection against investing everything one month before a large decline. Both facts are visible in the two runs.
What a skipped month actually costs
The engine assumes every month in the schedule is funded. Skip three of 120 months and reality has diverged from the page: $750 less principal was contributed, and each skipped dollar lost its own compounding window. At a 7% assumption, a dollar missed at month 60 would have grown by roughly 1.40 by month 120, so those three missed months represent closer to $1,050 of ending value if they fell mid-schedule. The exact figure depends on which months were skipped, because a missing early dollar loses more years than a missing late one.
To model irregular funding honestly, reshape the inputs rather than ignoring the gaps: shorten the years or reduce the monthly contribution to the average you actually hit. A schedule that contributes $250 nine months out of twelve is a $187.50 schedule wearing a $250 label, and running the calculator with the true number gives you a result you can plan around. The reverse error also worth flagging: rounding your contribution down to a comfortable round number and never typing the difference in. Over 120 months, $8 of monthly leakage is $960 of principal that never met the compounding.
How this calculator works
Formula
FV = initial x (1+r)^n + monthly x (((1+r)^n - 1) / r), with r the monthly return and n the months.
Worked example
$1,000 initial plus $250 a month for 10 years at 7%: $31,000 contributed grows to about $45,281, with $14,281 of growth.
Frequently asked questions
What is a DCA calculator and how does it work?
A DCA calculator is a free online tool that estimates the future value of your investments by simulating regular, fixed-amount contributions over time using compound growth based on your expected rate of return.
Do I need to create an account or share any personal data to use this tool?
No. This tool is entirely no-signup and runs in your browser, nothing is stored, shared, or sent to a server. Your inputs stay private and local to your device.
How accurate are the projections from this DCA calculator?
The projections are estimates based on the assumptions you enter, such as your contribution amount, frequency, and expected annual return. Actual results depend on market conditions and are never guaranteed.
Cite this tool
BoringToolsKit. “DCA Investment Calculator.” boringtoolskit.com/dca-investment-calculator/. Free to reference in articles, syllabi, and answer posts with a link.
Privacy: Inputs and results stay in this browser. Any future sponsored recommendation or advertisement will be clearly labeled and kept separate from the calculation.