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
ROAS
4.20
Break-even ROAS
2.22
Profit after ad spend
$4,450
Return on ad investment
89.0%
Read
Profitable after product cost
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter ad spend ($).
- 2Enter revenue attributed ($).
- 3Enter gross margin (%).
- 4Read your roas on the right — it updates as you type.
- 5Hit Share to keep the scenario or send it to someone.
About this calculator
A 3x ROAS sounds great until you subtract product cost. Break-even ROAS is simply the inverse of your gross margin — at 40% margin you need 2.5x just to stay level.
Worked example
Using the values the calculator loads with:
Inputs
- Ad spend: 5000 $
- Revenue attributed: 21000 $
- Gross margin: 45 %
Results
- ROAS: 4.2
- Break-even ROAS: 2.22
- Profit after ad spend: $4,450.00
- Return on ad investment: 89.0%
- Read: Profitable after product cost
What each field means
Inputs
- Ad spend ($)
- The ad spend used in the calculation, measured in $. Starts at 5000 $ so you have a working example on load.
- Revenue attributed ($)
- The revenue attributed used in the calculation, measured in $. Starts at 21000 $ so you have a working example on load.
- Gross margin (%)
- The gross margin used in the calculation, measured in %. Starts at 45 % so you have a working example on load. Accepted range: 1–100 %.
Results
- ROAS
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Break-even ROAS
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Profit after ad spend
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Return on ad investment
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Read
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the roas calculator work?
A 3x ROAS sounds great until you subtract product cost. Break-even ROAS is simply the inverse of your gross margin — at 40% margin you need 2.5x just to stay level. The underlying maths is: ROAS = Revenue ÷ Ad spend. Break-even ROAS = 1 ÷ Gross margin.
What do I need to enter?
3 values: ad spend, revenue attributed, and gross margin. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the roas result mean?
It is returned as a decimal number 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). ROAS Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/roas
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/roas" target="_blank" rel="noopener">ROAS Calculator — RevenueLab</a> (2026).</p>
Source: [ROAS Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/roas) (2026).