# Break-even ACoS Calculator

URL: https://aiadking.com/tools/break-even-acos-calculator
Updated: 2026-09-03

Free break-even ACoS calculator: enter selling price, product cost and Amazon fees to find the ACoS where an advertised sale breaks even. Aim below it.

Break-even ACoS is the ACoS where an advertised sale makes zero profit — advertising consumes exactly the margin you had after product cost and fees. The formula is (selling price − product cost − Amazon fees) ÷ selling price × 100. A $1,000 item with $400 cost and $200 fees has a 40% break-even ACoS, so you target below 40% to stay profitable.

## FAQ

Q: What is break-even ACoS?
A: Break-even ACoS is the ACoS at which an advertised sale makes neither a profit nor a loss — your advertising eats exactly the margin you had left after product cost and Amazon fees. Run ads below this ACoS and each sale is profitable; run above it and you lose money on every advertised order.

Q: How do you calculate break-even ACoS?
A: Break-even ACoS equals your profit margin before ad spend, as a percentage of the selling price: break-even ACoS = (selling price − product cost − Amazon fees) ÷ selling price × 100. If a $11 item costs $4.44 to make and $2.22 in fees, $4.44 margin remains — a 40% break-even ACoS.

Q: What ACoS should I target then?
A: Target an ACoS comfortably below your break-even so each advertised sale still leaves real profit, not just zero. How far below depends on how much margin you want to keep versus how aggressively you want to grow. Many sellers aim for an ACoS that leaves at least half their margin intact.

Q: Do I include all Amazon fees?
A: Include the per-unit costs that apply to a sale: the referral fee, FBA or fulfilment fee, and any per-unit storage or shipping you carry. This calculator takes one combined fees figure, so add them up first. The more complete your fee figure, the more accurate your break-even ACoS.

Q: How does AIAdKing use my break-even ACoS?
A: In AIAdKing you set a target ACoS, and the nightly cycle moves bids toward it on the official Amazon Ads API — never blindly, always with a logged reason and a shadow-mode preview. Set your target below your break-even and the automation works to keep advertised sales profitable. It is a flat $29/month with no commission on ad spend.