Ad Viewability: What To Know and Possible Solutions

Ad Viewability: What To Know and Possible Solutions

Advertisers are always trying to calculate the effectiveness of their campaigns. They ask, what worked, what didn’t, which creatives elicited the biggest response, what sites did their ads perform best on, etc. There’s another metric that is at the baseline of evaluation. Before figuring out if the campaign was a success, there’s something way more basic to ask – was the ad seen? That’s where ad viewability comes into play.

Table of Contents

  • What is  ad Viewability
  • Why Most Ads are not Seen
  • Things Publishers Can Do to Increase Ad Viewability on their Site
  • Things Advertisers can do to increase viewability
  • NMM’s Approach to Viewability

What is  ad Viewability

Ad Viewability refers to how visible an ad is by a user, literally, how much of and how long, if at all, did a user see it.

In 2014 the IAB set the standard for what is considered a viewable ad. 

An ad’s pixels need to be 50% in view for 1 second to qualify as viewable.

Videos need to be 50% in view and play for 2 consecutive seconds to be viewable.

IAB Standards of Viewability

Considering these low standards one might assume viewability to be a done deal. Yet according to a Comscore report, viewability still hovers around 55%. Meaning almost half of all ads served are never seen. That’s a lot of waste.

Why Most Ads are not Seen

One might think that if an ad was called, that means an ad was seen, but that’s not the case. Every page will have a set amount of ad inventory. For illustration purposes, let’s say a site has a banner on the top, a vertical rail on the side, and a third on the bottom. When the page first loads, most code has all the ads called and served. But what if someone opens a page, glances at the top, and clicks out, never scrolling at all. In that case, the vertical side ads and the one of the bottom, while served, and paid for, were never viewed by the user.

It’s important to realize this concept– not all ads are created equally. Every space will have a different value depending on how likely it is that someone will view the ad. There’s little point in advertising if there’s no one there to see it. In this case, there’s a clear answer to the age-old question, “if a tree falls in the forest and no one hears it does it make any noise?” No – it does not.

This may seem like an advertiser’s problem, but viewability affects publishers too. It’s easy for a publisher to say “This is the deal, take it or leave it.” However, advertisers may choose to put their budgets in sites with higher viewability ratings. 

Things Publishers can to do increase ad viewability on their site

  • Consider ad formats offered and incorporate more viewable formats into the site.  375 x 50 ad units most viewable at an average 94% viewability rate according to a 2018 Google study. Followed by 360 x 50 ad units at 92% viewability. 320 x 100 is at the bottom of list with a viewability of 47%.
  • Reconsider ad placement Contrary to popular belief, above-the-fold ad placement doesn’t always equal most viewable. The most viable space is right above the fold, not at the top. People scroll fast and often miss the first ad served.
  • Sticky ads are more viewable because they are on the page longer. Publishers should consider adding in rails, or sticky bottom ads that follow along as users scroll. 
  • Using heat maps, publishers can find high engagement spots on the site, and place an ad nearby. It’s smart to capitalize on users’ behaviors by hanging out where they already are.
  • If a site has content carousels, add an ad among those spaces. They have higher click through rates than average.
  • Less is more. It may be a little counterintuitive but less cluttered spaces are more viewable and therefore more profitable. This is where a yield manager comes in, finding the balance between more ad inventory and profitability.

Another thing to realize is different industries have very different viewability rates. Publishers should know their industry’s average so they can calibrate expectations and create attainable goals.

Things Advertisers can to do increase viewability

  • Higher Bids – when advertisers set their ceiling to relatively low CPMs the only placements they’ll be able to bid on with any chance of winning  are likely less desirable, below the fold placements on websites. Advertisers should try bidding higher to access better placement.
  • Simplify the creative – allowing the page to load faster. If the ad loads too slow, the viewer may have already scrolled past it by the time it shows up. If an ad is video or rich media advertisers should consider changing it to HTML 5 and compressing the file size.
  • Considering different industries have different viewability averages, advertisers should  advertise in a favorable vertical. The top three are reference, online communities, and games, the bottom three are real estate, news, and food & drink
  • Sign a PMP. By curating and selecting the sites that an advertiser’s creatives appear in is the only sure-fire way to increase viewability. Instead of leaving it up to chance, and bidding higher CPMs in the hope that it’ll land in better spaces, advertisers should take control of their advertising budget and put together a PMP that benefits them and minimizes ad waste.

NMM’s Approach to Viewability

NMM offers exclusive PMPs to advertisers, maximizing their ad spend. Regarding viewability, NMM’s viewability is 75% in the open market and can be as high as 90% with PMPs. Credit is due to to our four pronged approach: 

  1. Injection – our sophisticated algorithm, only calls for ads to be served as a person scrolls, and doesn’t fill it all at the header (This does not affect cumulative layout shift [CLS])
  2.  Speed of stack – We are always balancing the trade off between the necessity of speed and revenue. We tailor to each specific clients to ensure that an ad is served quickly and is seen.
  3. Generally maintaining code and stack – We are particular when choosing partners for websites. Depending on the vertical and other variables, some stack partners have different speeds that may hinder the speed of the ad. For each website there’s an initial two week period of yield optimization with continual check up.
  4. AI – NMM utilizes artificial intelligence to determine what the best time to load an ad.  Taking into account the speed of the ad and the behavior the user, AI configures the best time to call and serve an ad for the highest viewability.


Esther Kurtz