How to Calculate Your Break-Even ACOS on Amazon
What Is Break-Even ACOS?
Your break-even ACOS (Advertising Cost of Sale) is the maximum percentage of your revenue you can spend on ads before losing money. If your ACOS is above this number, every sale is costing you profit.
Most sellers guess this number — or worse, ignore it entirely. AdsPilot calculates it automatically for every ASIN.
The Formula
Break-Even ACOS = (Net Margin / Sale Price) × 100Example:
- Sale Price: $29.99
- Cost of Goods: $8.50
- FBA Fee: $4.20
- Referral Fee (15%): $4.50
- Net Margin: $12.79
Break-Even ACOS = ($12.79 / $29.99) × 100 = 42.6%This means you can spend up to 42.6% of your revenue on ads before breaking even.
Why Most Sellers Get This Wrong
Many sellers set a flat ACOS target (like 25%) across all products. But a 25% ACOS might be highly profitable for one product and deeply unprofitable for another — depending on margins.
Product A: 40% margin → 25% ACOS = 15% profit ✅
Product B: 20% margin → 25% ACOS = -5% loss ❌
The only way to optimize correctly is to calculate break-even ACOS per ASIN.
How AdsPilot Automates This
AdsPilot lets you enter your real product economics once — cost of goods, FBA fees, referral fees, VAT — and automatically calculates the break-even ACOS for each ASIN.
Every bid adjustment our AI makes is based on this number, not a generic target. The result: campaigns that protect your actual profit margin, not just your ACOS percentage.