About this tool
Make the result useful—not just precise-looking
Estimate the advertising efficiency a product must achieve before ad spend consumes its contribution profit. This calculator separates percentage payment fees from fixed non-ad costs.
How to use it
- Enter revenue per order and all non-ad variable costs.
- Add the payment fee rate and your desired profit margin.
- Calculate the maximum ad spend and required ROAS.
Useful for
- Setting a paid acquisition guardrail
- Comparing products with different contribution margins
- Planning a target-profit campaign
Assumptions
- ROAS means revenue divided by advertising spend.
- Payment fees apply to order revenue.
- The target margin is a share of revenue after all entered costs and advertising.
Limitations
- ROAS does not include lifetime value, organic halo effects, or fixed overhead.
- Attribution windows and platform-reported revenue may differ from realized revenue.
Common questions
Frequently asked questions
Is a lower break-even ROAS better?
Generally, yes. It means the product can tolerate more ad spend per unit of revenue, assuming the same attribution and cost definitions.
What if the contribution is zero or negative?
There is no sustainable positive ad spend at those inputs, so a break-even ROAS cannot be calculated.
Does this calculate MER?
No. It calculates product-level ROAS. Marketing efficiency ratio usually compares total revenue with total marketing spend.