Active View is a Google technology used to measure if an impression was viewable and for how long.
Active View tags track the viewability of ads served by Google Marketing Platform, which helps you determine how likely it is that an ad was actually seen by a user.
What's considered a "viewable" impression?
A display ad is considered viewable when:
- At least 50% of the ad is visible for at least 1 second and the ad is less than 242,500 pixels (970 x 250).
- At least 30% of the ad is visible for at least 1 second and the ad is 242,500 pixels (970 x 250) or greater.
A video ad is considered viewable when at least 50% of the ad is visible while the video is playing for at least 2 consecutive seconds.
Why measure viewability?
Measuring viewability helps advertisers better assess the value of different impressions, since not all impressions are equally likely to be seen. For example, consider a placement at the bottom of a webpage. If a user needs to scroll down to see the bottom of the page, the user might not see the ad before navigating away from the page. Yet for a user with a larger screen, the entire page might appear in a viewable space—which means the ad is visible, too. Both scenarios count as impressions, but only viewability tracks whether the impression was actually seen by the viewer.