Viewable impressions are valuable impressions

Naturally, viewable ads are more valuable to advertisers. Nonetheless, many ads are never seen by a user at all. This of course eliminates the possibility for the user to be able to interact with the ad and kind of defeats the point for the ad to be called and displayed in the first place.

What is a viewable impression?¹

An impression is considered viewable when it has appeared within a user’s browser and had the opportunity to be seen. The Interactive Advertising Bureau (IAB) defines a viewable impression as an ad that meets the following criteria:

• For ads up to 242 000 pixels, 50% of the ad’s pixels must visible in the browser window for a continuous one second.
  
• For larger ads (greater than 242,000 pixels, for example a 970x250 ad), 30% of the ad’s pixels must visible in the browser window for a continuous one second.
  
• For in-stream video ads, 50% of the ad’s pixels must be visible in the browser window for a continuous two seconds.

Pretty straightforward so far, right?² Yet a third of all digital ads cannot be seen by a user, because they are never within the parameters of the screen. This happens when the ad is position below the fold, and the user never scrolls down, when the user closes the page before the ad loads, and so on. One in three impressions are never viewed by the user - that is a pretty shocking number. And so it’s time to make a change.

Google has recently launched a new feature called ‘Viewable CPM’³ which allows publishers to set a CPM for ads that were ‘viewable’. This shows the big role viewability is starting to play. Knowing this, it is good to prepare now by improving the viewability of your ad slots and thereby increasing the value of your display inventory in the long run. Once the majority of your inventory is deemed viewable, you will be in a great position to earn more revenue. That is, advertisers focus their spend on viewable impressions and so publishers with the most viewable inventory will be in the best position to attract and capture lucrative brand advertiser dollars. Hence the importance of being seen.

Using the DFP Query Tool publishers already have access to the Active View metrics which give more insights on the viewability of your ads. Together with your development or tech team you can make some adjustments to your site to ensure the viewability improves on pages where it is low.

The first step is to focus on increasing the measurable impressions, because you can't count what you haven't measured. Some factors can prevent the tag from capturing viewability data. For example, ad inventory cannot be measured if there is:

• Render blocking CSS;
  
• Custom JavaScript;
  
• Cross-domain i-Frame.

Once your inventory is measurable – and the percentage of measurable impressions for all your ad inventory is close to 100%, the second step, is to make your ads more viewable.

Viewability can be improved by:

• Using tall ads rather than wide ads – with tall ads there is more tolerance for a user to scroll up or down while the majority of the ad can remain within view.
  
• Putting ads closer to the fold and closer to the content so that they’ll be more in line with where the users are going and are more likely to be looking and spending their time.
  
• Focussing on your site’s speed – if you have a slow website users may move away from the page before they’ve seen the ad, even though it has already been counted as an impression. You can check your site’s speed through Google’s Website Speed Testing Tool or PageSpeed Insights.
  
• Make sure the Google ad call happens as quickly as possible – you can check the waterfall diagram from Web Page Test or in Chrome Developer Tools. If the ad call comes too late, the user may have left the page before the ad is shown.
  
• You can also use ‘lazy loading’ or displaying ads below the fold. On a traditional web page it’s been the practice to request all ads at once, but all ads below the fold may never come into view if the user never scrolls down. Through lazy loading, the ad is only requested when the user scrolls down.
  
• For more examples, please have a look at the viewability best practices in the Google Help Centre or on the DoubleClick Blog.

In 2011, the Association of National Advertisers (ANA), the Interactive Advertising Bureau (IAB) and the American Association of Advertising Agencies (4A’s) came together as Making Measurement Make Sense (3MS) with the main aim to “fix digital measurement,” since this is “by all accounts the single greatest obstacle to marketer, publisher and agency”. They identified the currency shift from served impressions to viewable impressions as the single most important need. It is their intention to achieve a 100% viewability goal as soon as this is technically and commercially feasible.⁴

As mentioned earlier, currently, a high viewability percentage of the ads on your website makes your ad inventory more valuable. In the near future, however, viewability may become a real currency within the digital ecosystem of online advertising. This could mean that if you do not optimise your site now in order to improve the viewability of your ad spaces, you may lose out in the near future when impressions are only paid for once they’re deemed viewable.

So if you want to keep abreast in the ever-changing advertising digital landscape, improving the viewability of your ad slots should be your top priority.

¹For a basic overview on viewability, have a look at this infographic.
²Think you know it all? Take the viewability quiz now.
³NB: Please note that this feature is still in beta and is not available to all publishers yet, but it will be good to optimise your site accordingly to ensure you are ready when it is rolled out to all publishers.
⁴Source: State of Viewability Transaction 2015