Free order-economics calculator
Break-even ROAS calculator for eCommerce.
Calculate contribution before advertising, break-even CPA, break-even ROAS, target CPA and target ROAS from one representative order. Start with consistent revenue and variable costs, then choose the contribution you want left after ads.
Client-side calculations · Euro display · No email signup
Order-level economics
Derive an advertising allowance from contribution.
Break-even ROAS calculator
What can one order afford to spend on advertising?
The pre-filled values are a hypothetical example. Replace them with consistent order-level numbers from your business. Use the same currency for every field.
Use the inputs on a consistent basis.
Revenue and refunds
Use revenue net of sales tax, with a consistent discount and refund basis. If expected refunds are already removed from revenue, do not subtract the same loss again.
Shipping and variable costs
Shipping subsidy is delivery cost you absorb after shipping revenue. Include each product, payment, fulfilment and other variable cost once.
Order CPA and customer CAC
This calculator produces an order-level allowance. It represents new-customer acquisition cost only when each measured order belongs to one newly acquired customer.
The formulas.
| Output | Formula |
|---|---|
| Contribution before advertising | Revenue − all listed variable costs |
| Break-even CPA per order | Contribution before advertising |
| Break-even ROAS | Revenue ÷ contribution, when contribution is positive |
| Target CPA | Contribution − desired post-ad contribution |
| Target ROAS | Revenue ÷ target CPA, when target CPA is positive |
Worked example: the pre-filled values.
The hypothetical example uses €100 revenue and €60 total variable costs, leaving €40 before advertising. Reserving €15 after advertising gives a €25 target CPA. The break-even ROAS is 2.50× and the target ROAS is 4.00×.
These figures demonstrate arithmetic. They are not a recommended target or a client result. Fixed overhead and the desired profit buffer still need to be covered by the contribution remaining after ads.
When there is no positive allowance.
Zero or negative contribution
No positive advertising spend breaks even under those assumptions. The calculator reports the affected limits as unavailable.
The desired buffer uses all contribution
If the desired post-ad contribution equals or exceeds contribution, there is no positive target CPA or target ROAS.
Questions about this guide.
Are the inputs sent to a calculation service?
The calculator script processes values in your browser and does not send them to a calculation service.
Is contribution the same as net profit?
No. It is revenue after the variable costs included here. The amount left after advertising still needs to cover fixed overhead and any desired profit.
Should I enter the displayed ROAS directly into Google Ads?
Not automatically. This is an order-economics model. A bidding decision also needs reliable reported values, attribution context, conversion volume and business constraints.
Put the result back into the account.
Need to decide what to fix first?
The €650 eCommerce Diagnostic reviews the wider account and turns the evidence into a prioritised roadmap and review call. Ongoing management is scoped around catalogue, markets and implementation needs.
Written by Andrei Visan.
I’ve worked hands-on with Google Ads since 2010. This resource explains a diagnostic approach, not a claim of specific client results.
Find the next useful account action.
Bring the store and the acquisition problem. We can confirm whether the €650 diagnostic or another next step fits.