Profit Geeks

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Ad Spend Calculator.

Enter five numbers from your last full month of trading. The calculator returns CPA, ROAS, ad spend as a share of revenue, the contribution left after media and overheads, and the break-even ROAS your business actually needs to clear margin.

$

Total media spend across all ad platforms last month.

$

Mean revenue per converted order or signup.

Best estimate is fine. Use platform-attributed orders if your CRM is not connected.

%

Revenue minus cost of goods, divided by revenue. Most $2M-$20M brands sit between 30 and 70 percent.

%

Salaries, software, rent, freight, processing fees as a percentage of revenue.

Outputs

Monthly ad revenue

$57,600

0

ROAS

2.88x

0

Cost per acquisition

$63

0

Ad spend / revenue

34.7%

0

Contribution after ads + overhead

$3,040

0

Break-even ROAS

2.50x

Lowest ROAS that clears your margin and overhead.

0

Verdict · Break-even territory

A 2.9x ROAS looks workable on the surface but rarely survives the full P&L. Most operators sitting here are working hard to stand still.

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How to read the numbers

CPA, ROAS, and the share-of-revenue test.

Cost per acquisition is the simplest sanity check. ROAS tells you whether the channel is making money. Ad spend as a share of revenue is the sustainability test. If the share crosses 25 percent without margin to support it, you are scaling on borrowed time.

Break-even ROAS is the number agencies skip.

Most agency dashboards report platform ROAS without referencing the actual margin structure of the business. The break-even ROAS shown here is calculated from your gross margin and overhead. Below it, you are losing money on every order. Above it, every additional dollar of spend compounds.

Next step

Want this number defended in writing?

We run a two-week Tracking Audit that reconciles platform-reported revenue against your CRM and surfaces where the leak is. Output is a written report with a prioritised fix list.

See what the audit coversRead the long-form analysis

Frequently asked

Five questions we get on the strategy call.

What is a good ROAS for paid advertising?

There is no universal good ROAS. The number that matters is your break-even ROAS, calculated from your gross margin and overhead. A 3x ROAS is profitable for a 50 percent margin business and a loss-maker for a 20 percent margin business. The calculator on this page returns both numbers side by side.

How do I calculate cost per acquisition (CPA)?

CPA is monthly ad spend divided by the number of new customers or orders that ad spend produced in the same month. For early-stage funnels with delayed conversion, use a 28-day or 90-day cohort instead of the same month.

What is break-even ROAS?

Break-even ROAS is the lowest return on ad spend that covers your gross margin and fixed overhead. The formula used here is 1 divided by (gross margin percentage minus fixed overhead percentage). Ad spend below break-even is a cost centre, not a growth lever.

What share of revenue should ads be?

There is no fixed answer, but a sustained share above 25 percent without strong margin to support it is the threshold where most operators in the $2M to $20M band start losing money quietly. The calculator surfaces this number explicitly so it can be tracked over time.

Why does my agency report a higher ROAS than my CRM?

Three common reasons: cross-platform deduplication is double-counting conversions, view-through windows are inflating attribution, or the platform-side conversion event is firing on /thank-you pageviews rather than real orders. A two-week tracking audit usually closes the gap to within five percent.