Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Balance with dollar cost averaging
$128,433
Balance investing it all at once
$133,178
Lump sum advantage
$4,745
Amount invested per month
$5,000.00
DCA gain
$68,433
Lump sum gain
$73,178
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter total to invest ($).
- 2Enter months to spread it over.
- 3Enter expected annual return (%).
- 4Enter total horizon (years).
- 5Read your balance with dollar cost averaging on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Lump sum beats DCA about two-thirds of the time simply because markets rise more often than they fall. DCA is a behavioural tool for reducing regret, not a return optimizer.
Worked example
Using the values the calculator loads with:
Inputs
- Total to invest: 60000 $
- Months to spread it over: 12
- Expected annual return: 8 %
- Total horizon (years): 10
Results
- Balance with dollar cost averaging: $128,433.05
- Balance investing it all at once: $133,178.41
- Lump sum advantage: $4,745.37
- Amount invested per month: $5,000.00
- DCA gain: $68,433.05
- Lump sum gain: $73,178.41
What each field means
Inputs
- Total to invest ($)
- The total to invest used in the calculation, measured in $. Starts at 60000 $ so you have a working example on load.
- Months to spread it over
- The months to spread it over used in the calculation. Starts at 12 so you have a working example on load. Accepted range: 1–60.
- Expected annual return (%)
- The expected annual return used in the calculation, measured in %. Starts at 8 % so you have a working example on load. Accepted range: -20–30 %.
- Total horizon (years)
- The total horizon (years) used in the calculation. Starts at 10 so you have a working example on load. Accepted range: 1–40.
Results
- Balance with dollar cost averaging
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Balance investing it all at once
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Lump sum advantage
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Amount invested per month
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- DCA gain
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Lump sum gain
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the dollar cost averaging (dca) calculator work?
Lump sum beats DCA about two-thirds of the time simply because markets rise more often than they fall. DCA is a behavioural tool for reducing regret, not a return optimizer. The underlying maths is: Balance = Σ contribution × (1 + monthly return)^(remaining months).
What do I need to enter?
4 values: total to invest, months to spread it over, expected annual return, and total horizon (years). Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the balance with dollar cost averaging result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Dollar Cost Averaging Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/dollar-cost-average
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/dollar-cost-average" target="_blank" rel="noopener">Dollar Cost Averaging Calculator — RevenueLab</a> (2026).</p>
Source: [Dollar Cost Averaging Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/dollar-cost-average) (2026).