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Ad Viewability

What is Viewability?

The IAB UK defines viewability as
‘an online advertising metric that aims to determine whether an ad impression had the opportunity to be seen or not.’
It is important to note that, if an ad is viewable, it doesn’t guarantee that an ad was seen by a consumer - in the same way, that you cannot guarantee someone sees an OOH ad when they walk past a billboard.

How viewability is measured?

A viewable impression indicates that a display ad was viewable when served. More specifically, the IAB and MRC define a viewable impression as one that’s at least 50% visible for at least one second.

To be more specific, viewability is a metric that tracks if at least half of a display ad has the chance to be seen in the viewable portion of a browser window for at least one continuous second.

Why viewability is so important?

Since its launch in 2010, viewability has been an essential KPI for advertisers. Imagine how many ads users are exposed daily but how many of it’s actually seen and not only served? It could be that the ad is loading at the bottom of the page and where the user never scrolls so in this case the ad was not viewed. 

Advertisers always want to drive results and make sure their campaigns are successful and viewability metrics helps them ensure that.

With a lot of ads not getting viewed by real users, this makes advertisers waste millions of dollars in ad spend each year. And towards a publisher, this decreases the value of their ad inventory. 

The industry is seeing an uplift in more campaigns being booked for viewable impressions because it can prove results for them so the direction about the industry preference is clear.

How higher viewability will benefit my site?

Let’s be honest, viewable impressions are not cheap! This is the reason site owners should be focusing to improve their inventory and make sure that most of the ads can be viewed.

What are best practices for viewability?

There are a few ways to optimize towards better viewability on your site: 

  • Lazy loading. Lazy load is a method when the ad is served when necessary. This means that if the ad is below the fold it won't be served until the user starts scrolling and triggers an algorithm that the ad will be viewed. Sounds great! Well, guess what, your site is covered here since Venatus lazy load ad placements on your site. (Lazy Load)
  • Ad Placement. Making sure that ad placements are positioned correctly on the page. That said, we recommend having at least 1-2 ad placements above the fold which will ensure the ad is always seen. This should be done respecting user experience of course. Viewability relies on an ad being at least 50% visible for 1 continuous second. Ad placements directly above the fold help maximize both of these factors.
  • Ad Size: Taller ad sizes tend to have the highest viewability. Look for opportunities to run higher viewability sizes with high CPMs. This would be 300x600, 160x600 etc.
  • Page Optimization: Ensure optimal UX with device-optimized pages, responsive design, page speed, and implementing asynchronous and lazy loading when applicable. 
  • Responsive layouts or create mobile-optimized sites to ensure ads are displayed correctly cross-screen.

So what viewability shall I aim for?

Ideally, your site viewability should be 80% +

This benchmark, set up by the industry, is increasing every year, so that’s why it’s very important to optimize towards this metric and make sure your inventory has good quality.

Best Practices:

Optimize for ad placement: The position of the ad is strongly correlated with its viewability. The most viewable position for an ad is right above the fold, not at the top of the page. But that doesn’t mean below-the-fold placements are a complete waste. Content that holds a user’s attention has the highest viewability.