CPE

Cost Per Engagement is a pricing model where payment is tied to a defined interaction with the ad or creative rather than a click or a conversion. The qualifying engagement is set by the platform or advertiser — a video watched to a threshold, an expanded ad unit, an in-app event, or interaction with a playable creative.

Buyers meet CPE mostly on social platforms and app campaigns where advertisers want proof of attention, not just impressions. It is useful for warming audiences cheaply before retargeting, since engaged users convert better downstream. The pitfall is optimizing for the engagement itself: platforms will happily find users who engage with everything and buy nothing. Treat CPE campaigns as a top-of-funnel feeder and judge them by eventual cost per FTD, not engagement price.