ACoS

ACoS (Advertising Cost of Sales) is a core metric in Amazon Advertising that helps sellers and brands measure the efficiency of their ad campaigns.

It’s calculated as:

ACoS=Ad Spend​×100 / Ad Revenue

For example:
 If you spent $20 on ads and earned $100 in sales → your ACoS is 20%.

What it tells you:

• Lower ACoS usually means higher profitability
• Higher ACoS may mean you’re overpaying for sales, unless it’s a strategy for product launches or ranking

👉 ACoS is especially useful when:

• Evaluating individual campaigns or keywords
• Setting break-even or target margins
• Scaling up profitable ads and cutting wasteful ones

ACoS vs. ROAS:

• ACoS is spend ÷ revenue (lower is better)
• ROAS is revenue ÷ spend (higher is better)

What’s a “good” ACoS?
 It depends on your product margin:

• If your profit margin is 30%, then ACoS under 30% means you're profitable
• Many brands aim for break-even ACoS during launches, and profitable ACoS for mature campaigns

ACoS is visible in:

• Campaign Manager in Amazon Ads Console
• Reports (e.g. Sponsored Products, Sponsored Brands)