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Amazon advertising economics · Free · No signup

Amazon Break-even ACoS Calculator

Estimate the advertising-cost percentage that would consume the remaining contribution profit in your unit-economics scenario.

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Break-even ACoS

Find the ad-spend ceiling

Defaults are only starting assumptions. Replace them with the fees, fulfilment, returns and costs from your own store or marketplace statement.

Live scenario

Break-even ACoS

35.7%

Approximate maximum ad spend before this order reaches zero contribution profit.

Percentage fee
$6.00
Return exposure
$1.20
Profit before ads
$14.29
Ad cost entered
$4.00

This is a planning estimate, not an official fee quote. Marketplace, payment, fulfilment, tax, refund and advertising rules vary by account, category and country.

Shareable result

35.7%Break-even ACoS

$14.29 contribution profit before ads on Amazon marketplace. Sharing includes only the displayed result label and value; raw calculator inputs and local detail are not added to the shared URL or analytics event payload.

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What this calculator answers

What is the approximate ACoS ceiling before this unit reaches zero contribution profit?
How do COGS, FBA or fulfilment costs, referral fees and returns change that ceiling?
How much pre-ad contribution profit is available to fund acquisition?

From calculator to recurring workflow

Stop rebuilding the same spreadsheet every week.

The free tool is for one scenario. Solarc Labs paid workflows are for repeated analysis, saved evidence, team handoff and automation.

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Independent tool: Solarc Labs is not affiliated with or endorsed by Amazon, Shopify or WooCommerce. Brand names are used only to describe common seller workflows. Outputs are planning estimates based on the figures you enter and are not tax, customs, accounting, advertising or marketplace-fee advice.