Free Amazon ACoS Calculator

Find your ACoS and compare it to your break-even threshold.

ACoS alone doesn't tell you if a campaign is profitable — you need to compare it against your break-even ACoS, which equals your profit margin before advertising. If your margin is 30% and your ACoS is 20%, you're still profitable on ad-driven sales; if ACoS climbs above 30%, those sales are now losing money even though they're generating revenue.

Worked Example

Example: You spend $150 on ads that generate $750 in attributed sales. ACoS = $150 / $750 × 100 = 20%. If your product margin before ads is 35%, this campaign is profitable (20% < 35% break-even).

Formula

ACoS % = Ad Spend / Ad-Attributed Revenue × 100
Break-even ACoS = Profit Margin % (before ad spend)

Frequently Asked Questions

What's a good ACoS?
It depends entirely on your margin — there's no universal "good" number. The right benchmark is your own break-even ACoS, which equals your pre-ad profit margin.