**What is ACoS and how is it calculated?**

Amazon **ACoS** (*Advertising Cost of Sale*) measures the efficiency of your advertising campaign. It is the ratio of ad spend to ad revenue (in %). In other words, ACoS shows how much of every dollar that was earned with advertising was spent on the ad campaign. You can calculate ACoS using this formula:

**ACoS = Ad Spend ÷ Ad Revenue * 100**

*Example 1*:

A campaign has generated $254 of advertising sales. The ads during this campaign cost $63.

→ ACoS = 63 / 254 * 100 = 25%. I.e. for every dollar made, 25 cents have been spent.

*Example 2*:

Your sponsored product has had a total of $2 costs for all of its clicks, and made a total of $10 in sales.

→ ACoS = 2 / 10 = 20%. I.e. for every dollar made, 20 cents have been spent.

**Understanding ACoS**

The following articles can help obtain a better understanding as to why the ACOS is a central metric to measure the performance of your Sponsored Products, as well as how you can define what a "good" ACOS is: