Google finds that only one in two video ads it serves across the web have the chance of ever being seen
There's a number of reasons why ads are deemed not "viewable," such as users never scrolling to the part of the page where the ad appears, ads loading in a background, or users simply scrolling past the ad too quickly to count as an impression (the industry standard for a viewable video impression is that 50% of an ad's pixels are visible on the screen for two consecutive seconds or more.)
A study conducted by Google, using its ActiveView technology to look at video ads on YouTube, and also video ads it serves across the web (desktop, mobile, and tablet) using its ad platform DoubleClick found just 54% of video ads on average across the web are viewable.
On YouTube, 94% of video ads are viewable.
There's a reason for the discrepancy here: YouTube ads are served in the big YouTube video player - ads on the rest of the web can be served in far smaller players.
Location really matters too: YouTube ads are served in a prominent position, whereas ads on the rest of the web can be positioned in places on the page less likely to be seen.
The YouTube data in Google's study also included mobile app data, whereas its research didn't look at other mobile apps, which could have potentially skewed the results. More than half of YouTube views are on mobile devices, and Google also found that video ads are "significantly more viewable" on mobile and tablets than on desktop.
The study is a clear advert for YouTube's video advertising offering, but it does provide some useful information for publishers and advertisers as to how they can increase the viewability of their ads. Essentially it advises to make the player big, and to position it front and center at the top of the page ... a bit like YouTube, really.
It follows research released by Google in December, where it admitted that 56.1% of the impressions served on Google display platforms never had the chance of being seen.
Once again Google is trying to put a message out to the market that it accepts ad viewability is a problem, but that it is taking responsibility and working to improve its numbers.
It's worth pointing out that while Google is serving some ads that are not viewable, the bulk of its advertising is served on a cost-per-click or cost-per-acquisition basis - so advertisers only pay if a user engages with an ad. On YouTube, it has a "TrueView" ad format where advertisers only pay if a user watches a video ad for at least 30 seconds or to the end of the video (whichever is less.)
Across the industry, advertisers and media owners are shifting to only paying for video ads - rather than just served impressions - so improving viewability across the web is becoming a priority for the biggest digital properties. Those headline viewability numbers might look bad, but so long as advertisers aren't paying for those unviewable ads, it's becoming less of concern for them, but it's paramount for publishers to improve the visibility of ads across their websites and apps so they don't miss out on revenue.