Using the standards set by the Media Rating Council (MRC) and Interactive Advertising Bureau (IAB), that 50% of an ad’s pixels must be visible on screen for at least two consecutive seconds for it to be counted as viewable, a Google research study of ad viewability on its platforms revealed that average viewability of video ads across the web was just 54%.

Ad viewability on YouTube came out as being significantly higher, at 91%.

One of the main reported reasons for video ads not being seen was that 76% were running in a background tab while users looked at something else. The remainder were scrolled off screen or abandoned within two seconds.

Viewability rates were found to be higher on mobile devices — interim guidance was released last week outlining the same criteria for mobile viewability — at 83%, and tablets ( 81%), than on desktop computers ( 53%).

The full study can be accessed here.