ACoS · Advertising Cost of Sale
Advertising Cost of Sale (ACoS) is the share of advertising-driven revenue you spend on advertising, worked out as ad spend ÷ ad sales × 100.
If you spend $25 on Amazon PPC and it brings in $100 of sales, your ACoS is 25%. A lower ACoS means your ads are working harder.
What counts as good depends on your margins. An ACoS below your break-even point, where ad cost equals the profit on a unit, means the campaign makes money. Above it, you're paying to win sales at a loss, which sellers sometimes do on purpose to gain rank.
Why it matters
ACoS tells you whether your advertising is making or losing money, which makes it the core number for managing an Amazon PPC budget.
Related terms
Guides that use this term
- How to Calculate Profit Margins: Amazon FBA vs Dropshipping
A step-by-step guide to working out your true profit margin, covering the full Amazon FBA fee and cost stack, the ad-cost reality of dropshipping, and the break-even maths that decides whether a product is worth selling.
- How to Advertise Your Products: Amazon PPC & Paid Social
A practical guide to advertising your products: how Amazon PPC and paid social for dropshipping work, how to start without wasting budget, and how to tell whether your ad spend is actually making money.
- How to Set Up Your First Amazon PPC Campaign
A beginner's guide to Amazon PPC: the main ad types, automatic versus manual campaigns, how to structure your first Sponsored Products campaign, and how to use the data it produces.
- How to Lower Your ACoS (and When Not To)
How to lower your Amazon ACoS without killing sales: cutting wasted spend, tightening targeting and bids, and knowing when a higher ACoS is the right call for rank and long-term profit.
See ACoS on real products
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