Flexible Ad Size Guidelines for Retail Media Networks - Open for Public Comment

As Retail Media continues to grow, traditional ad formats often fail to integrate smoothly within retailer websites. This has led to a proliferation of bespoke formats which, while sometimes effective, can drive unnecessary complexity, strain advertiser resources, and hinder scalability across networks.

To solve this, IAB Europe’s Flexi Ad Formats Proposal, based on a solution developed by Tesco Media and refined through IAB Europe’s standards workshops, introduces a simplified and flexible approach to static display ad sizes.

What's in the Proposal?

• A core set of four flexible ad sizes designed to work seamlessly across mobile, tablet, desktop, and mobile app environments.
  
• Clear implementation guidelines and code templates provided to retailers and ad tech partners, making adoption straightforward.

Key Benefits

• Broader access to brand programmatic budgets through more standardised formats
• Improved operational efficiency by reducing format fragmentation
• Enhanced consumer experience through consistent, viewable placements

Call for Feedback

Our Flexible Ad Size Guidelines for Retail Media Networks is now open for public comment. Your input will help ensure the guidelines meet the needs of retailers, brands, and partners across the industry.pos

• View the Flexible Ad Size Guidelines for Retail Media Networks here.
• Share your feedback with us directly by emailing retailmediastandards [at] iabeurope.eu
• Read our press release here.

The deadline to provide your input is Friday, 14th November 2025.