Use this tool to evaluate the efficiency of your Amazon advertising campaigns. ACoS (Advertising Cost of Sales) helps you understand how much of every dollar earned from sales is spent on advertising.
Your Calculated ACoS:
0%
Advertising Cost of Sales (ACoS) is a key metric used by KDP authors to measure the performance of their Amazon Advertising campaigns. It represents the ratio of ad spend to target sales, expressed as a percentage.
ACoS = (Ad Spend / Sales) x 100
Suppose you are running a Sponsored Products campaign for your paperback. Over the last 30 days, you spent $40 on clicks. Those clicks resulted in 20 book sales totaling $200 in revenue.
A good ACoS is one that is lower than your net profit margin. If your royalty rate is 70% (after print/delivery costs), any ACoS under 70% means you are technically profitable on those ad-attributed sales.
Your royalty percentage directly defines your break-even point. If you earn $3.50 on a $5.00 ebook, your margin is 70%. Your break-even ACoS is therefore 70%. If your ACoS is 75%, you are losing money on each sale.
No. While ACoS measures ad efficiency, you should also track Total ACoS (TACoS), which compares ad spend to total sales (organic + ads). A rising organic rank can justify a higher ACoS in the short term.
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