Glossary
ACoS
Advertising Cost of Sales: how much you spend on ads for every unit of sales those ads generate.
FormulaACoS = ad spend ÷ ad-attributed sales × 100
Definition
ACoS is Amazon's primary efficiency metric for Sponsored Products, Sponsored Brands and Sponsored Display. A 25% ACoS means 25 cents of advertising for every euro of attributed sales. Amazon attributes a sale to an ad if the shopper clicked it within 7 days (Sponsored Products) or 14 days (Sponsored Brands and Display) before buying.
There is no universal good ACoS. The only benchmark that matters is your break-even ACoS, the margin left after cost of goods and Amazon fees. Below it, the paid sale itself is profitable; above it, you are buying rank or awareness and must expect to earn it back through organic sales.
ACoS is best used at keyword, placement and campaign level for day-to-day decisions. For the health of the whole business, TACoS (spend over total sales) is the better number.
Example
Product price 29.99 €, cost of goods 7.50 €, Amazon fees 9.20 €. Margin before ads 13.29 € → break-even ACoS 44%. A campaign at 22% ACoS leaves 6.60 € profit per paid sale.
How we use it
We set an ACoS target per ASIN below its break-even, separate brand terms (very low ACoS) from generic terms, and report ACoS alongside TACoS every month.
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What is your break-even ACoS?
Enter your price and costs. See the ACoS you can afford before advertising stops being profitable.
Get the full analysisPre-ad margin
€13.29
Break-even ACoS
44.3 %
Our target for you
≤ 10 %
What is a good ACoS on Amazon?
Anything below your break-even ACoS on mature products. Across accounts we manage, generic keywords typically run 15 to 30% and brand keywords under 10%, but the right number depends on your margin.
Why is my ACoS so high?
Usually one of four reasons: a listing that converts below the category average, broad or auto campaigns without negatives, bids set for position instead of margin, or brand and generic terms mixed in one campaign.
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