What is it, and why is it important?
Viewability is simply a digital advertising metric that reports on impressions that are seen by humans. An impression is considered viewable when it has appeared on a browser and had the opportunity to be seen. The IAB (Interactive Advertising Bureau) measures viewable impression when 50% of the ad’s pixels are visible in the browser for a continuous 1 second for standard ads. For bigger ads, 30% of the ads pixels are visible in the browser. For video in-stream ads, 50% of the ads pixels need to be visible in the browser for a continuous 2 seconds.
Viewability is an essential metric to determine campaign effectiveness. This measures whether an ad reached the target audience or not because an ad that isn’t viewed can’t deliver the message or make an impact. Publishers also value viewability to demonstrate the value of their inventory to advertisers. They can show that their ads are being seen, which can help increase revenue.
Advertisers can use viewability metrics to hold publishers accountable for delivering ads that are actually viewable to users by running placements above the fold or optimizing their site for faster loading speeds. Viewability data can identify what ad placements or formats are driving the highest viewability rate and adjust strategies to improve performance.
Placement
Above the fold ads are the ads that appear on the person’s screen without any scrolling, while below the fold ads require the user to scroll down to see. Above the fold ads tend to have higher viewability rate naturally since they are already on the screen but it’s important to note that if all the ads ran above the fold it can lead to ad fatigue and reduce overall viewability. People could develop ad blindness and ignore the ads altogether. Below the fold ads may have a lower viewability rate but can still be effective. If the user is already engaged with the content that brought them below the fold, there is a chance the user is already invested in that page.
Format
Static Ads are likely to have a higher viewability rate than video ads because users are more likely to click on them rather than video ads. Video ads can be blocked or skipped unless the user is already engaging, and content is relevant to the user. Viewability and ad placements are closely linked, and brands should consider sizes, formats and placements to maximize viewability rate.
It's important to keep in mind that viewability does not guarantee engagement or impact. A viewable ad may not lead to a click or conversion, it just means that it has a chance of catching the user’s attention and delivering your brand message. Measuring effective of a campaign is not just based on viewability, advertisers should also track click through rates, conversion rates and engagement rates.