EPC in affiliate programs stands for "Earnings Per Click." It is a metric used to measure the average earnings an affiliate generates each time someone clicks on their affiliate link. You can calculate EPC by dividing the total earnings by the total number of clicks. EPC helps affiliates evaluate the performance of different programs and choose the most profitable ones. A higher EPC means the program is likely to generate more revenue per click. Affiliates often use EPC to compare programs and decide where to focus their marketing efforts for the best returns.