What is ACoS?

ACoS stands for Advertising Cost of Sale. It's the ratio of your total ad spend to the revenue generated by those ads, expressed as a percentage. For example, if you spent $20 on ads and earned $100 in sales, your ACoS is 20%. It's one of the most fundamental metrics in Amazon PPC management and a go-to signal for gauging whether your campaigns are pulling their weight.

How to Calculate ACoS

ACoS = (Total Ad Spend ÷ Total Ad Revenue) × 100. Keep in mind that ACoS only reflects revenue directly attributed to ad clicks—organic sales driven by improved rank or brand awareness are not included. That's why many sellers also track TACoS (Total Advertising Cost of Sale), which divides total ad spend by total revenue including organic, for a more complete view of advertising efficiency.

What is a Good ACoS on Amazon?

There's no universal answer—it depends on your margins, goals, and where the product is in its lifecycle. A practical framework:

• Break-even ACoS equals your profit margin (e.g., 30% margin = 30% break-even ACoS)
• Your target ACoS should sit below break-even to remain profitable
• New launches can tolerate higher ACoS to gain ranking and early reviews
• Mature products with strong organic rank should aim for a lower, tighter ACoS
• Category benchmarks vary widely—research your specific niche before setting targets

ACoS vs. TACoS: What's the Difference?

ACoS only measures ad-attributed sales, while TACoS divides total ad spend by total revenue—including organic. TACoS gives a truer picture of how advertising is impacting your overall business. As organic rank improves over time, TACoS typically decreases even if ACoS holds steady, which is a healthy sign that your ads are building sustainable momentum.

Tips to Improve Your ACoS

• Pause high-spend, low-converting keywords and redirect budget to performers
• Use negative keywords to block irrelevant traffic before it eats your budget
• Optimize your listing—better conversion rates reduce ACoS naturally
• Adjust bids by placement, time of day, and device using available bid modifiers
• Segment campaigns by match type (broad, phrase, exact) for tighter control

Monitoring ACoS & Campaign Changes

ACoS can fluctuate from bid changes, competition, or listing updates. Real-time tracking helps maintain profitability.