# Marketplace Advertising Break-Even Calculator

> Marketplace ad break even calculator: find break even ROAS and ACOS from product price, platform fees, and shipping costs. Free, editable rates, no signup.

- **Canonical URL:** https://boringtoolskit.com/marketplace-ad-break-even-calculator/
- **Category:** Seller & Business
- **Evidence level:** authored-methodology
- **Reviewed:** July 2026
- **Last verified:** 2026-09-20
- **Privacy:** Inputs and results stay in this browser unless the page clearly labels an external request.

## How it works

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

- 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.

## Common 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.

## Related tools

- /amazon-seller-fee-calculator/
- /etsy-fee-profit/
- /ebay-fee-profit-calculator/

## Sources

- [Target ROAS bidding](https://support.google.com/google-ads/answer/6268637?hl=en)
- [Advertising cost of sales (ACOS)](https://advertising.amazon.com/library/guides/acos-advertising-cost-of-sales)

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*Local planning estimate. Verify current terms, rates, and policies before acting.*