You may be wondering how to measure the success of your advertising campaigns. One way is with Amazon Ads' average cost per sale (ACoS). This metric tells you what percentage share each keyword has when combined across all ads for that campaign and can help determine which keywords are most profitable based on their earnings potential. For example, if I spent $15 but only received 50% revenue from those searches because customers had multiple options before them or other factors blocked conversion opportunities such as high competition regions--then my ACoSpend would come out at 30%.