Earnings per click (EPC) is a metric used in affiliate marketing that calculates the average amount of revenue earned per click on an affiliate link. It is an essential metric for affiliate marketers to understand because it shows the expected earnings per click. EPC is calculated by dividing the total affiliate marketing earnings by the total number of clicks on those links. It is typically run through pay-per-click (PPC) ads. EPC is one of the most valuable pieces of data for affiliate marketers as it gives insight into whether or not a product is worth the effort, time, and resources. It is often displayed by affiliate marketing networks to help affiliate marketers evaluate and compare their earnings potential to that of other merchants. By tracking EPC, affiliate marketers can tune their efforts to maximize their pay-per-click income.