New Ad Format: IAB Flexible Ad

August 15, 2018

New Ad Standards

The IAB recently released new flexible ad specs as a part of its New Ad Portfolio. This release replaces all previous creative display guidelines for mobile and desktop. As today’s need for responsive design grows rapidly, this new set of standards will accommodate all devices and screen resolutions. This ad portfolio is based on HTML5 technology and includes guidelines for new digital content experiences such as augmented reality (AR), virtual reality (VR), social media, etc.

You can download the final IAB new portfolio specs here.

According to the IAB, the new ad units are based on aspect ratio rather than fixed pixel sizes. Ad units with flexible sizes allow for scalable ad delivery across multiple screen integrations with responsive website design. The FLEX specs aim to shift from static dimensions and move towards creative that will maintain its resolution regardless of the user’s device or publisher’s platform. This makes for a more cohesive digital experience across a variety of devices.

Additionally, these new specs incorporate LEAN Principles ( Lightweight, Encrypted, AdChoices supported, and Non-invasive advertising,) with the intention of creating a better user experience and decreasing intrusive ad delivery. The new ad portfolio emphasizes user respect, choice, and control in the advertising experience, which is why formats such as popups and interstitials are no longer perceived as compliant with the new guidelines. Subsequently, page load time will decrease and provide a more seamless browsing experience for viewers.  

How to Comply

As a result, we’ve released a new Flexible Ad Format. The Flexible Ad format allows users to create ads in compliance with the new standards. Commonly used ad sizes like the 728x90 can be replaced by a flexible aspect ratio based on ad size such as 6:1 or 4:1.  A 300x250 could be replaced with a 1:1, or a 300x600 could be replaced by a 1:2.  Full-screen sizes based on screen aspect ratios could be 16:9 (horizontal), 9:16 (vertical), etc. Users can choose from a selection of default ratios, or can create their own custom depending on the ad parameters.

Adventive's Flexible Ad Unit Default Sizes

To learn how to create a Flexible Ad using our platform, check out this article from our Knowledge Base.

Because Adventive is publisher first, our goal is to ensure that our partners get the most from this guideline update. As always, for questions regarding the new IAB Flexible Ads (or anything else)  contact us at

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