Profit planning

Ecommerce profit & break-even ROAS calculator

Use revenue, product costs, fulfilment, payment fees, overhead and paid-media share to estimate your break-even ROAS, target ROAS, MER and maximum CAC.

No signupRuns in your browserUpdated 18 July 2026
Core principleRevenue is not profit.

Your viable acquisition target changes with every point of margin, fulfilment cost and repeat value.

Target ad budget = revenue − costs − target profit
Scenario calculator

Enter one typical month

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Use the best blended estimate available, not one platform’s claim.
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Team, software, premises and other fixed overhead.
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Your target scenario

Commercially viable

Target view
—Target ROAS
—Break-even ROAS
—Target MER
—Maximum CAC
Maximum ad budget at target margin—
Current estimated operating profit—
Current blended paid ROAS—
Use this as the floor for channel decisions.

Compare this commercial target with platform performance and new-customer data.

Discuss the scenario
Keep this result Copy a concise summary, print it, or choose to add it to a consultation request.
Discuss this result

This is a planning estimate, not accounting advice. It treats the entered percentages as applying to net revenue and does not model tax, working capital, stock timing or customer lifetime value. Confirm definitions with your finance team.

What the calculator is showing

Break-even ROAS is the paid-attributed revenue required for each pound of advertising before the model reaches zero operating profit. Target ROAS adds the profit margin you want to preserve.

MER is advertising spend divided by total net revenue. It gives a blended view that is less vulnerable to multiple platforms claiming the same order.

Why your real target may be different

  • New and returning customers can support different acquisition costs.
  • Product categories can have materially different margins and return rates.
  • Cash timing, inventory risk and discounting are not visible in a simple monthly model.
  • A first order may be unprofitable but commercially viable when repeat purchase is reliable and measured.

How to use the result

  1. Agree the cost definitions with finance.
  2. Calculate targets separately for important product or customer groups.
  3. Compare store-level MER with platform-attributed ROAS.
  4. Use experiments and new-customer reporting before increasing budget.
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