What is cost per engagement (CPE)?
Cost per engagement (CPE) is a marketing metric that shows the average amount of money spent to acquire a single desired action — or engagement — by a customer. Engagements can include actions like clicks, views, likes, shares, and comments. To calculate CPE, divide a campaign’s total cost by the number of engagements it generates.
Mobile app advertisers can use CPE campaigns to influence high-quality, valuable users by driving profitable and targeted behaviors in the app, which include actions like completing a signup, reviewing a product, or making a purchase. To incentivize user actions and maximize ad budget, CPE campaigns often come in the form of reward-focused campaigns which reward app users with online discounts, virtual goods, or premium content. These campaigns usually show high conversion rates and a greater return on ad spend (ROAS) since they reward users and require them to opt in.
How to calculate CPE
CPE is calculated by dividing the total amount spent by the total measured engagements. For example, let’s imagine that your highest lifetime value (LTV) users complete registration for an in-app account. If you spend $5,000 on a CPE campaign that measures registrations for an in-app account, and it leads to about 500 engagements, your CPE comes out to $10 per engagement.