Break-even ACoS is the ACoS at which your ad spend uses up all of your profit on an ad-attributed sale. It equals your profit per unit before advertising, divided by your selling price. Enter your costs to get break-even ACoS and a target ACoS that keeps a margin.
price − COGS − FBA fee − (price × referral %) − other costsprofit before ads ÷ price × 100break-even ACoS − desired profit margin %Every unit you sell has a fixed set of costs before advertising: what you paid for the product and inbound shipping (COGS), Amazon's FBA fulfillment fee, the referral fee (a percentage of price, often 15% but it varies by category), and anything else per unit like packaging or storage.
Whatever is left is your profit before ads. If you spend exactly that amount on ads for each ad-attributed sale, you break even. Expressed as a share of price, that is your break-even ACoS.
Most sellers don't want to break even, so subtract the margin you want to keep. That gives a target ACoS you can hand to a bid optimizer. Launch campaigns may run above break-even on purpose; just set a time limit.
Ads are profitable on attributed sales while ACoS stays under 43.3%; aim for about 33% to keep a 10% margin.
Set a target ACoS and AdSpark's bid optimizer steers every keyword toward it, reviews search terms, and logs each change so you can reverse it. 14-day free trial.
Break-even ACoS = (price − all per-unit costs before advertising) ÷ price × 100. It's the same as your pre-advertising profit margin.
Usually not. Break-even means zero profit on ad-attributed sales. Set your target below break-even by the margin you want to keep, unless you're deliberately investing in a launch or rank push.
Amazon's Revenue Calculator in Seller Central shows the FBA fulfillment fee and referral fee for a specific ASIN. Fees change periodically, so recheck them at least once a year.
No. It's measured per ad-attributed sale. If ads also lift organic rank and sales, a campaign above break-even can still be profitable overall, which is why many sellers watch TACoS too.