Marketplace Advertising Break-Even Calculator

Calculate break-even ROAS and ACOS after product cost, marketplace fees, payment fees, fulfillment, shipping, returns allowance, and target profit.

Rate fields are editable assumptions. Verify current marketplace and processor terms separately before using the result.

Results will appear here.

Planning estimate only. Platform fees, taxes, payment costs, and policies can change; verify current terms before pricing.

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How this calculator works

Reviewed July 2026

Formula

Percentage reserves = sale price × (marketplace fee % + payment fee % + returns allowance %) ÷ 100. Contribution before ads = sale price − percentage reserves − product cost − shipping − fulfillment − other fixed cost − fixed payment fee. Break-even ACOS = contribution before ads ÷ sale price × 100, and break-even ROAS = sale price ÷ contribution before ads when contribution is positive.

Worked example

At $50 revenue with $15 product cost, $2 shipping, $5 fulfillment, $1 other fixed cost, 15% marketplace fee, 3% payment fee, 5% returns allowance, and $0.30 fixed payment fee, contribution before ads is $15.20, break-even ACOS is 30.40%, and break-even ROAS is about 3.29×.

Assumptions to verify

  • Marketplace fee, payment fee, and returns allowance fields are user-entered planning assumptions and must be checked against current terms.
  • This model excludes attribution windows, lifetime value, taxes, and broader overhead unless you explicitly include them in the visible inputs.
  • A zero or negative contribution before ads means no ad spend can make the order profitable under the current assumptions.

Frequently asked questions

What is the difference between ROAS and ACOS?

ROAS is revenue divided by ad spend, while ACOS is ad spend divided by revenue. They describe the same relationship from opposite directions.

Why is the returns field an allowance instead of a prediction?

This calculator reserves a percentage of revenue for expected returns or refunds. It does not predict actual return behavior or claim marketplace-specific refund rules.

Does this calculator fetch current marketplace fees or ad data?

No. It uses only the visible assumptions you enter, so it stays deterministic, local, and independent of marketplace or advertising APIs.

Privacy: Inputs and results stay in this browser. Any future sponsored recommendation or advertisement will be clearly labeled and kept separate from the calculation.