Google Study Illustrates The Factors That Affect Ad Viewability

An increasingly large number of marketers are moving toward buying display ads on a viewable impression basis as opposed to by served impression. To help advertisers to understand what affects an ad’s viewability, Google analyzed its display ad platforms, including DoubleClick.

Google explained the reason for the study in its “5 Factors of Viewability” article. “It’s important to understand what factors affect ad viewability,” wrote Google. “We explored this by conducting a study of our display advertising platforms, including Google and DoubleClick. Here we size up five factors of viewability–from page position to ad dimensions and more.”

According to the IAB (Interactive Advertising Bureau) standard, a viewable impression occurs when at least 50 percent of an ad is in view for more than one second. Google’s new study analyzed display ads across web browsers on both desktop and mobile devices and discovered the following 5 key findings:

1. State of publisher viewability: The research found that a small number of publishers are serving the majority of the non-viewable impressions. While 56.1 percent of all impressions are not seen, the average publisher viewability is 50.2 percent.
2. Page position matters: Surprisingly, the most viewable position is not at the top of the page. Google’s study found that the most viewable position is actually directly above the page fold.
3. The importance of ad size: The study found that the most viewable ad sizes are vertical units, as they stay on the screen longer as users move around a page. The 120 X 240 unit had the highest viewability at 55.6 percent, while the popular 300 X 250 unit actually had the lowest viewability rate at 41 percent.
4. Viewability rates above and below the fold: While viewability rates above the fold were found to be higher than below the fold, it is nowhere near 100 percent. Likely due to fast scrolling by users, 68 percent of above-the-fold ads were considered viewable, while 40 percent of below-the-fold ads were viewable.
5. Viewability variance across industries: The study found that not all publishing verticals are the same when it comes to viewability. Reference was found to score the highest in viewability at 51.9 percent, while hobbies and leisure scored the lowest at an average of 44.8 percent.

The following chart illustrates Google’s overall findings for viewability variance across industries: