How to use this calculator
- Enter contribution margin before advertising (%).
- Choose a display currency, then select Calculate. Results also update after a brief pause while you edit.
- Read the result with the assumptions below. Export details or save a second scenario to compare your choices.
Formula and method
Assumptions and limitations
Margin must already account for variable product, payment, fulfillment and expected return costs. It must not include advertising twice.
Worked example
With contribution margin before advertising (%) = 40, break-even roas multiple is approximately 2.5.
What the result means
At the modeled break-even point, contribution profit exactly covers ad spend; fixed overhead is not additionally covered.
Common questions
How should I interpret break-even roas multiple?
At the modeled break-even point, contribution profit exactly covers ad spend; fixed overhead is not additionally covered.
What should I check before using this result?
Margin must already account for variable product, payment, fulfillment and expected return costs. It must not include advertising twice.
Methodology and transparency
Calculation specification reviewed on 2026-10-14. Mathematical implementation is tested against independent reference fixtures. This does not imply review by a licensed financial professional. Read the testing and precision policy.