Online ad viewability rises with interactivity, HTML5, mobile sizes

Sizmek, an ad management company, analysed viewability data from more than 240 billion impressions in 2014. Its main finding is that performance rises along with viewability. While not exactly surprising, the research validates the IAB’s recommendation that advertisers should aim for 70 per cent viewability in each campaign (meaning that for 70 per cent of the impressions in a campaign, at least half of the ad was in view for at least 1 second). The research also found that viewability rises for interactive ad formats, HTML5 ads versus Flash ads, mobile-specific ad sizes and ads served direct to publishers versus through programmatic means.


Viewability is one of the biggest challenges facing publishers, with the IAB trialling measures both in the US and Australia to get a better understanding of what counts as an ad being ‘viewed’.

The measures that the Interactive Advertising Bureau (IAB) came up with mean that online display ads are counted as ‘viewed’ if they have been on screen for at least one second and were at least 50% loaded. Video ads are likely to be counted as ‘viewed’ if they played for two seconds.


Alex White, VP of product strategy at Sizmek, said: “The specifics and definitions will no doubt continue to be debated, but the recent efforts at standardising viewability terminology move the industry toward a more transparent marketplace for digital ads, and our research backs that up.

“Clearly, measuring whether an ad is viewable gives the industry a starting point for trading in true engagement.”

In December last year Google found that more than half (56.1%) of all digital impressions of online ads are not seen.

The search giant found that a small number of publishers were serving most of the non-viewable impressions, causing the numbers to be skewed slightly higher. This means that overall 56.1% of all impressions are not seen, however the average publisher viewability sits at 50.2%.

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