Break-Even ACoS Calculator
The exact ACoS where an ad-driven sale stops making you money. Every formula is shown below — no email, no signup, no catch.
Your numbers (per unit)
Break-even ACoS
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Above this, every ad-driven sale loses money.
Contribution / unit
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Contribution margin
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Target ACoS to keep 15% net margin
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What your number actually means
Enter your numbers above — then I'll tell you what your break-even ACoS says about how much attention you can afford to buy.
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Break-even & target-ACoS benchmarks by category, plus the 5 profit leaks I check first. No spam — unsubscribe anytime.
Every formula, shown
Amazon referral fee = price × referral%
Total cost/unit = COGS + referral fee + FBA fee + other
Contribution/unit = price − total cost/unit
Contribution margin = contribution/unit ÷ price
Break-even ACoS = contribution margin
Target ACoS = break-even ACoS − net margin you want
Why it matters: ACoS on its own tells you nothing about profit — a "good" 25% ACoS is bleeding money on a thin-margin product and printing cash on a fat-margin one. Break-even ACoS is the line. Margin protection — one of the five pillars of the AMDC Growth System — is about knowing this number for every SKU and bidding to it.
Want this run across your whole catalog?
The Profit & Growth Teardown finds your break-even line on every SKU — and the exact dollars leaking above it. $500, credited toward your first month if we work together.
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Talk to Aleks directly, not an account manager. No pitch.