AdTech Buzzwords Explained - Viewability

We’ve already talked about some of the most popular AdTech terms you can hear around - data-driven advertising, omni-channel experience, ad fraud, cookies, etc. Now we turn the spotlight to "viewability" - one of the most important words in the vocabulary of online advertisers even before the age of programmatic media buying.

What is viewability?

Viewability addresses the main question advertisers ask themselves - "was my ad seen on the webpage that I payed for?". Was the ad placed on the bottom of the page seen, or was it posted on a pop-up window and the user didn’t see it, these are all questions describing issues related to viewability. And there is a difference between published and viewed - an impression is the ad being published on the web page, be it on the bottom or on the middle of the page. This impression is considered to be viewed only if the user actually scrolled down and saw the ad. Hence, viewability is the metric that helps advertisers track how many of their impressions were actually seen by users.

And here comes the tricky part - as of now there is no clear definition how to measure viewability. The Internet Advertising Bureau (IAB) states that an impression is viewable if at least 50% of it was visible for at least 1 second. In the same time, many vendors offering viewability solutions are using their own different methods and technologies to establish this, causing viewability to be an ongoing topic of heated debates.

If you’d like learn more on this topic, we recommend you check also Digiday’s article on Viewability.

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