The energy in the room was electric as the Interact 2025 mainstage opened on 21st May 2025 in Brussels with a powerful series of keynote presentations that set the tone for the day. Bringing together influential voices from across the digital advertising ecosystem and beyond, the morning sessions delivered fresh perspectives on the economic, technological, and regulatory forces reshaping our industry.
From unpacking the latest ad spend trends and hearing brand and publisher reactions to the AdEx results, to exploring the real-world impact of AI, the next evolution of Retail Media, and what it means to build a trusted digital roadmap, the morning was packed with thought leadership that challenged, inspired, and informed.
Capping off the morning sessions, we also had a powerful and deeply moving keynote from Anastasiya Baydachenko, CEO of IAB Ukraine, who delivered a sobering and necessary perspective with "Destroying Modern War Illusions".
Check out the mainstage morning highlights below:
In this opening keynote presentation, our Chief Economist, Dr. Daniel Knapp, set the scene on European Digital Advertising investment. Daniel revealed the top-level results from our hotly anticipated AdEx Benchmark Results for 2024, which now covers 30 European markets, to show where future advertising growth will come from.
Key highlights included:
Following Daniel’s presentation, we heard an advertiser’s perspective on digital investment and innovations. In this fireside chat Alison shared her insights on what Kraft Heinz is prioritising, detailing the channels and formats that are fuelling their growth and innovation. She addressed diverse critical issues such as creativity and brand building, the evolution of media spend and Metrics, while touching upon measurement, targeting, and attribution.
Next, we heard a publisher’s perspective. In his keynote address, Bernard covered key strategy pillars, such as content, distribution, and monetisation, while outlining the fundamental elements of a successful advertising strategy for premium publishers.
After a short coffee break, we came back to the mainstage to dive into the fascinating world of AI. This session demystified the AI space by covering trends, opportunities, myths, and misconceptions, as well as getting into practicalities. Forget the fluff. Dominique talked about real examples of companies using AI in new ways, and shared a live AI multi-tooling demonstration on smarter, faster, more creative work to reveal what the future of work looks like. Attendees learned how to bring AI into an organisation and drive transformation.
Next we turned to Retail Media, where Colin draw from his direct experience working with brands and retailers around the globe such as Barilla, Fonterra, Optimum Nutrition, Superdrug, Very Group Ocado (UK), Migros (Turkey), Cencosud (Chile), Terry White Chemmart (Australia) and the Warehouse Group (New Zealand) to address the hottest topics in this space today, including creativity, effectiveness, collaboration, and performance.
The IAB Tech Lab then took us through a deep dive into the highlights of its 2025 strategy and product roadmap, with a closer look at its Trusted Server Open Source Initiative. As browsers tighten their grip on the open web, the IAB Tech Lab’s Trusted Server Framework offers publishers a path to reclaim control, shifting key ad operations server-side to restore transparency, privacy compliance, and revenue potential.
To round off the morning sessions, we had a powerful and deeply moving keynote from Anastasiya, who delivered a sobering and necessary perspective with "Destroying Modern War Illusions". Her talk reminded us of the real-world impact of war on society and business, urging the industry to stay grounded, resilient, and purposeful as we navigate both progress and crisis.
After a morning of big-picture insights on the mainstage, the afternoon workshops at Interact 2025 offered attendees the chance to roll up their sleeves and engage in hands-on, in-depth discussions on the issues shaping the next chapter of digital advertising. Designed to foster focused dialogue and actionable outcomes, each workshop brought together expert speakers, curious minds, and innovative solutions.
From evaluating the current landscape of Retail Media and unlocking the potential of Privacy Enhancing Technologies (PETs), to forecasting the future of Connected TV and dissecting what’s working and what’s not, in digital measurement, these sessions were a testament to the industry’s commitment to continuous learning and evolution.
Check out the highlights from our afternoon workshops below:
In our dedicated retail media session, we walked attendees through the forces shaping Retail Media in Europe. Growth, advancements, and opportunities were all presented for attendees to truly understand the impact of Retail Media advertising.
The session started with our Industry Development & Insights Director, Marie-Clare Puffett, providing an overview of the Retail Media ecosystem, including key stats, and developments.
We then heard from Evangelia Mitoli, Sales & New Business Development Manager at Douglas Marketing Solutions GmbH, who spoke about the role of first-party data in Retail Media and showcased how brands can benefit from DOUGLAS‘ Data Solutions along the whole customer journey.
The session concluded with an interactive panel discussion moderaated by Jason Wescott, Global Head of Commerce Solutions at GroupM and Chair of IAB Europe’s Retail & Commerce Media Committee who was joined by:
Our next workshop explored the transformative potential of Privacy-Enhancing Technologies (PETs). Through a keynote by Sebastian Grantz, Global Data & Privacy Manager, Industry Relations at Google, and an engaging panel discussion on 'Tackling PETs from different perspectives: Policy, Browser-Platforms, Industry', attendees gained insights into the latest PETs solutions and their practical applications.
Attendees left with a deeper understanding of emerging policy recommendations and the opportunities available for industry-wide collaboration on data sharing standards.
Sebastian moderated the panel discussion and was joined by:
In this session, David Cohen, CEO at IAB, led an exploration into the next generation of CTV. Attendees gained insights into the forces driving greater sophistication across buying and measurement, discovered the latest innovations propelling the channel forward, and learned how the industry is addressing measurement challenges.
The discussion also highlighted key investment trends and predictions for future growth, while offering inspiration and actionable strategies for raising the bar across the CTV ecosystem.
David moderated the session as was joined by:
In this final workshop of the day, we brought everything together to discuss advancements and focus areas in digital advertising measurement. Hosted by ExchangeWire’s CEO, Rachel Smith, a panel of measurement experts shared their views and forecasts on what we can expect from CTV, to audience measurement.
Rachel was joined by:
As the day progressed, Interact 2025 shifted into a more focused gear with a series of expert-led afternoon masterclasses designed to dive deep into the most critical and complex areas of digital advertising. These intimate, high-impact sessions offered attendees the chance to gain practical knowledge, explore emerging solutions, and walk away with actionable takeaways they could immediately apply within their organisations.
From navigating the balance between privacy and innovation, to kickstarting your AI journey, addressing audience measurement in the context of evolving EU policy, and putting the TCF into practice, these masterclasses delivered real value. Sustainability also took centre stage, with a session on how to reduce emissions across the digital supply chain and build a more sustainable future for our industry.
Our first masterclass explored the potential implications of the European Commission’s 2025 work programme for the digital advertising sector, with a focus on regulatory simplification and competitiveness. Key topics included the withdrawal of the draft ePrivacy Regulation, signalling possible changes to the EU’s privacy framework, and the upcoming review of the digital acquis. The discussion also examined the proposed European Data Union Strategy, aimed at fostering scalable data sharing while upholding robust privacy and security standards, and what all of this could mean for the future of digital advertising in Europe.
This session was moderated by Jacob Dexe, Public Affairs Manager, IAB Sweden, who ws joined by:
Dominique returned to the stage in the afternoon to help attendees cut straight to the good stuff, helping to inform and align teams on adopting AI in everyday tasks.
The session included a live demonstration on how to work smarter and more creatively with AI multi-tooling, using practical tasks from the audience, all run in AI multi-tooling format. It also offered a quick crash course on AI frameworks and best practices for research, data analytics, and content creation.
This session explored the crucial role of audience measurement within the evolving EU digital policy landscape. Key areas of focus included: the impact of the European Media Freedom Act (EMFA), the debate between independent and proprietary measurement systems, and upcoming regulatory developments. The masterclass also emphasised the increasing political significance of audience measurement for both commercial needs and public interest goals, advocating for industry collaboration and proactive engagement with regulatory oversight.
Speakers:
As the digital advertising ecosystem continues to evolve under increasing regulatory scrutiny, ensuring effective and consistent compliance with the EU Data Protection Legal Framework remains a shared challenge. This panel examined the role of the TCF Compliance Programmes in providing participants with structured ways to meet their legal requirements through audits, technical guidance, and dedicated enforcement procedures.
The session was moderated by Ninon Vagner, Privacy Director at IAB Europe who was joined by:
This masterclass provided an essential update on Ad Net Zero Europe’s progress in reducing advertising’s carbon footprint, highlighting key milestones and the importance of collaboration across markets. It unpacked the challenges and opportunities within the five Ad Net Zero actions and shared the latest on the Global Media Sustainability Framework.
IAB Europe then dived deep into the digital side of this transformation, introducing key tools that can help you start cutting emissions today. The session concluded with an interactive audience Q&A, ensuring attendees left with practical, actionable insights.
Speakers:
Brussels, Belgium, 29th May 2025 – IAB Europe has announced the official launch of its Retail Media Certification Programme for retailers, following a successful initial pilot phase. This first-of-its-kind initiative aims to set a new standard for transparency, consistency, and accountability in Retail Media measurement across Europe. Two leading retailers - Nectar360, Sainsbury’s retail media business, and Albert Heijn - are in the final stages of the compliance audit and are set to become the first certified retailers under the programme.
In parallel, IAB Europe is also launching a new beta phase of the certification programme tailored specifically for Ad Tech players that support the retail media ecosystem, expanding the programme’s impact across the broader Retail Media ecosystem.
The Retail Media Certification Programme is designed to help retailers and technology providers validate their measurement practices against industry-agreed standards. For retailers, the full certification is now available, following months of collaboration, feedback, and pilot testing during the beta phase. This rigorous process includes an independent audit to assess compliance with measurement standards in both on-site and off-site Retail Media reporting.
Commenting on the launch, Jason Wescott, Global Head of Commerce Solutions at GroupM and Chair of IAB Europe’s Retail & Commerce Media Committee, said, “A lack of standardisation has long been a barrier to retail media investment. We've addressed this by delivering both measurement standards and now a certification programme to give advertisers confidence in the networks they work with. I’m delighted Nectar360 and Albert Heijn are the first to soon be certified and look forward to welcoming ad tech participants into the next phase.”
Amir Rasekh, Managing Director, Nectar360, also said, “Our clients are at the heart of everything we do, and we’re continually working in pursuit of greater transparency, consistency, and accountability to deliver better outcomes for them. This is an important piece of work by IAB Europe, which is why we were determined to be among the first two businesses to be certified. We also understand the need to standardise and play our part in removing complexity in the retail media market for clients, whilst also continuing to innovate and develop the sophistication of our measurement practices according to their needs.”
Max de Jong, Sr. Manager Media Performance & Consumer Insights at Albert Heijn Retail Media Services, said, “We’re proud to be one of the first retailers globally to take part in this pilot. It’s another important step forward in our journey to build AH Retail Media Services into a mature, measurable, and trusted media organisation.”
The certification programme has been developed in consultation with leading industry experts, including members of IAB Europe’s Retail & Commerce Media Committee, Retailer Leaders Council, National IABs and Federations, brands, agencies, and retailers. It also aligns with global standards where possible, including ongoing coordination with the Media Rating Council (MRC) to ensure harmonisation of accreditation efforts across the Atlantic.
Independent auditors for the programme include Alliance for Audited Media (AAM), Audit Bureau of Circulations (ABC UK), and Centre d'Étude des Supports de Publicité (CESP).
Retailers interested in achieving certification can now apply here. Meanwhile, Ad Tech partners are also invited to register interest in joining the beta phase using the same form here, where they will receive guidance on the certification framework and contribute feedback to help refine the process ahead of a full rollout in 2026.
For more information about the Retail Media Certification Programme, view our FAQs here, and visit the IAB Europe website here.
To learn more and gain further insights into the Retail Media Certification Programme, join us at our upcoming Retail Media Certification Townhall on 12th June at 15:00 CET. Register here.
The digital advertising community is preparing to gather once again on the sun-soaked shores of the French Riviera for the Cannes Lions Festival 2025, taking place from 16th to 20th June. Known for its blend of creativity, insight, and inspiration (and a splash of rose and glamour), the festival remains one of the most anticipated moments in the industry calendar.
This year, IAB Europe is excited to return to Cannes to connect with leaders, spark conversations, and showcase the pivotal work we’re driving across Retail Media, Connected TV, and more.
Our Chief Economist, Daniel Knapp, Industry Development & Insights Director, Marie-Clare Puffett, Marketing & Communications Director, Lauren Wakefield, and Data Analyst & Sustianability Lead, Dimitris Beis, will be on the ground and available to share insights, discuss industry developments and opportunities, and highlight how our initiatives can support your strategic goals. If you'd like to meet with the team, get in touch!
Here’s a sneak peek at what’s in store for our time in Cannes:
Global Media Sustainability Framework v1.2 Launch
Join us at the Sustainability Hub, Palais (next to the Debussy Theatre - Palais pass required) for the release of GMSF v1.2.
This is the first major update to the framework filling major data gaps – especially in digital – and equipping advertisers, agencies, and media owners with voluntary industry standards to estimate and reduce emissions across six main media channels.
Speakers include our very own Data Analyst and Sustainability Lead, Dimitris, alongside:
Coffee & Commerce in Cannes with PubMatic
In partnership with PubMatic, we are hosting an exclusive breakfast and roundtable discussion.
Attendees will be among the first to hear key findings from IAB Europe’s Attitudes to Retail Media survey and learn how advertisers, agencies, and Retail Media Networks across Europe are approaching investment, growth, and innovation. They’ll also gain fresh insights from PubMatic on how the open internet is powering the next wave of commerce media and what it means for the future of the industry.
Addressability & Measurement Round Table & Networking Session with Verve
With thanks to event hosts Verve, we will be hosting an informal roundtable and networking event for our Addressability Working Group members. Participants can expect to join industry stakeholders to hear their perspectives on the current addressability and measurement landscape in Europe. Think lively conversation with practical insights on how the landscape will develop.
If you’re working in the addressability space and are interested in attending, please vist the event page here and RSVP here to attend.
Connected TV (CTV) Measurement Roundtable Brunch with Nielsen
In partnership with Nielsen, we will host an exclusive roundtable discussion, bringing together CTV Leaders from our CTV Working Group to delve into the pivotal area of Connected TV (CTV) measurement within the European landscape. This focused roundtable will provide a valuable forum for working group members to connect, exchange insights on the latest measurement challenges and innovations, and build meaningful relationships.
If you’re working in the CTV space and are interested in attending, please email the team below.
If you are heading to Cannes and would like to connect with the team, please reach out to:
Marie-Clare Puffett
puffett [at] iabeurope.eu
Lauren Wakefield
wakefield [at] iabeurope.eu
Daniel Knapp
Dimitris Beis
beis [at] iabeurope.eu
Brussels, Belgium, 22nd May 2025 - IAB Europe, the leading European-level industry association for the digital marketing and advertising ecosystem, is pleased to announce the appointment of a new Board of Directors. Elected during the hybrid Annual General Meeting (AGM) held in Brussels on 20th May 2025, the new Board will serve a two-year mandate and support the execution of IAB Europe’s strategic priorities.
The Board is composed of 10 National Federation Members and 10 Corporate Members, representing a cross-section of Europe’s digital advertising value chain, from leading publishers and media owners to ad tech providers and agencies. This multi-stakeholder composition ensures balanced representation across the ecosystem and reinforces IAB Europe’s role as the unified voice for digital advertising in Europe.
The new Board will oversee the implementation of IAB Europe’s 2025 work plan, which centres on four strategic pillars:
National Federation Board Members:
Corporate Member Directors:
Townsend Feehan, CEO of IAB Europe, commented: "This is a transformative period for our industry, marked by evolving regulation, rapid technological innovation, and increasing demand for sustainable practices. Our 2025 board brings together an exceptional group of leaders who are committed to collaborating across national and corporate perspectives to build a responsible, transparent, and future-ready digital advertising ecosystem. The team and I look forward to working closely with them to deliver meaningful progress for our members and the wider industry."
Double-digit growth marks another year of acceleration, with Social, Video, and Retail Media leading the way.
Brussels, Belgium, 21st May 2025 – IAB Europe, the leading European-level industry association for the digital marketing and advertising ecosystem, today released its 2024 AdEx Benchmark Report live at Interact 2025, revealing that the European digital advertising market has achieved double-digit growth, surpassing €118.9 billion in annual revenue for the first time in constant currency terms.
Now in its nineteenth year, the AdEx Benchmark Report remains the definitive source for advertising expenditure insights across Europe. This year’s edition includes data from 30 national markets - welcoming Portugal for the first time - to deliver a fully harmonised digital advertising investment total for the region. Notably, the Report also offers, for the first time, a comprehensive overview of Retail Media as a category.
Despite macroeconomic uncertainty in 2022, the European digital advertising market rebounded strongly in Q4 of 2023, continuing this trajectory into 2024. The latest data reveals double-digit growth of 16%, with total investment reaching €118.9 billion, reinforcing the continued investment by advertisers in the channels and formats shaping the innovative digital advertising ecosystem. This is also the strongest growth recorded since 2011, with the exception of 2021’s digital bonanza in the wake of the COVID-19 pandemic.
Key Growth Drivers:
Market Highlights:
A Dynamic 2024 Outlook
Commenting on the results, Daniel Knapp, Chief Economist at IAB Europe, said: "Last year, we forecast a 10% growth rate for 2024, which felt ambitious at the time. Yet, the European digital advertising market exceeded these expectations, growing by 16% in constant currency terms and crossing the €100 billion milestone to reach €118.9 billion for the first time. Even using current exchange rates, the market grew by 14.9% – a testament to digital advertising's integral role in European advertising strategies. The end of 2023 marked a clear upward trend, which continued into and through 2024. While 2024 shaped up to be another healthy year, early forecasts for 2025 suggest a renewed period of volatility and that the ‘rollercoaster’ may be restarting. Driven by macroeconomic uncertainty and geopolitical tensions, including the impact of new EU tariffs, advertisers are likely to adopt a cautious, ‘wait-and-see’ approach, prioritising measurable outcomes and performance over broad experimentation.”
The full AdEx Benchmark Report 2024 is available to download on IAB Europe’s website here and provides granular insight into digital advertising trends across 30 European markets.
Join the Conversation
To explore the findings in more detail, join IAB Europe’s virtual AdEx Benchmark Townhall on 28th May at 12:00 CET, where Daniel Knapp will dive into the trends and what the results mean for the future of digital advertising in Europe. Register here.
With Interact 2025 just around the corner, we’re continuing to highlight some of the stand-out sessions scheduled at this year’s event. This time, we’re diving into the cutting-edge world of Privacy-Enhancing Technologies (PETs), brought to you by our headline sponsor, Google.
Taking place on 20th-21st May in Brussels, Interact is the European conference bringing together leaders from across the digital advertising ecosystem under one roof. With a central theme of ‘Digital Skylight – Clarity and Purpose for 2025 and Beyond,’ this year’s event will explore the economic, social, and industry forces shaping and driving the future of our industry.
As privacy regulations tighten and user expectations evolve, PETs are poised to be a critical element in ensuring the future of digital advertising remains both innovative and privacy-respecting. At Interact, one of the standout sessions will shine a light on how PETs are paving the way for a more secure, collaborative, and transparent digital ecosystem.
Find out more about the agenda here, and discover what’s in store for this session below:
Unlocking PETs: A Key Workshop at Interact 2025
In our afternoon workshop “Unlocking Privacy Innovation: PETs Solutions and Recommendations for the Digital Ecosystem,” experts will provide a deep dive into the potential of PETs to revolutionise the way digital advertising handles data privacy. The session will feature a keynote by Sebastian Grantz, Global Data & Privacy Manager at Google, and a panel discussion tackling PETs from multiple angles - policy, platform, and industry.
Of the event, Sebastian said, "I'm thrilled to be in Brussels for IAB Europe's Interact conference, diving into the exciting world of Privacy-Enhancing Technologies and the new business opportunities they unlock!"
A 360° View: Tackling PETs from Policy, Platform, and Industry Perspectives
The workshop will explore how PETs are evolving to meet the needs of privacy-conscious users and organisations alike. Moderated by Sebastian Grantz, the panel will include:
Peter Craddock, Partner at Keller and Heckman LLP, offering legal insights on the intersection of PETs and data protection laws like GDPR.
Alex Cone, Senior Product Manager, Privacy Sandbox at Chrome, shedding light on how browsers like Chrome are shaping the future of PETs.
Sylwia Sajewska, Country Manager Germany at Decentriq, who will highlight the ways PETs enable secure data collaboration across industries.
Don’t miss out on this critical session at Interact 2025, where industry leaders will explore the transformative potential of PETs and their role in shaping the future of digital privacy.
Last Chance to Get Your Tickets for Interact 2025
Interact 2025 isn’t just about our immersive workshops and thought leadership content on stage. It’s also the place to connect, collaborate, and build the future together, and we can't wait to welcome you to Brussels.
With less than a week to go, don’t miss out on our limited time offer for 20% off: Use code iab20eu at checkout and get 20% off your ticket!
We’re just one week away from Interact 2025, happening on 20th-21st May at nHow Brussels – and this is your final chance to register with a 20% discount!
🎟️ Register now and use code iab20eu at checkout to save: Register for Interact 2025
Under the theme ‘Digital Skylight – Clarity and Purpose for 2025 and Beyond’, Interact 2025 will bring together the brightest minds in digital advertising for two days of bold ideas, actionable insights, and game-changing conversations.
From policy and privacy to retail media and innovation, our agenda is built to inspire action and equip you with the knowledge you need to navigate the year ahead.
In a fast-evolving regulatory landscape, how can we strike the balance between privacy and progress? This essential session – “Policy in the Spotlight: Balancing Privacy and Innovation in Europe’s Evolving Regulatory Landscape” – features leaders from Microsoft, NOYB, Acxiom, and more.
Join Sebastian Grantz (Google) for a keynote on the future of PETs, followed by a panel and audience Q&A exploring real-world applications and innovations in privacy-first advertising.
Retail Media is exploding across Europe. Don’t miss insights from Colin Lewis (Retail Media Works) and Heike Schneider (Douglas Marketing Solutions) as they unpack growth opportunities and practical next steps.
Be the first to hear the results of the AdEx Benchmark 2024, presented by Daniel Knapp – a deep dive into the trends and market growth shaping the digital landscape in Europe.
Hear from leaders across top brands, publishers, tech platforms, and agencies. Walk away with practical takeaways to drive your business forward.
It’s not just about great content – it’s also about the connections you’ll make. From opening night drinks to our rooftop closing party at Rooftop 58, you’ll have plenty of opportunities to network with Europen leaders.
⏳ Final seats are going fast – don’t miss your chance to be part of Europe’s premier digital advertising event.
Register now and use code iab20eu for 20% off
Retail Media has firmly established itself as one of the most dynamic and fastest-growing spaces in digital advertising. As investment surges and innovation accelerates, the demand for consistent, transparent, and scalable measurement has become a top priority.
To meet this need, IAB Europe has produced two measurement standards: the Retail Media Measurement Standards for On and Off-Site in Europe and, in collaboration with the IAB U.S., the In-Store Retail Media Definitions and Measurement Standards. These initiatives aim to harmonise measurement practices across the region, providing a shared foundation for evaluating performance and driving continued growth.
View the Standards Below
Developed by members of IAB Europe’s Sustainability Standards Committee, this blog dives into the complexities of ad file compression, exploring how reducing file sizes may or may not translate into measurable carbon savings, the challenges of quantifying network emissions, and the broader implications for performance and infrastructure efficiency.
Thank you to the following contributors for sharing their expertise:
Dimitris Beis, Data Analyst & Sustainability Lead, IAB Europe
Andrew Hayward-Wright, VP Media Operations, SeenThis
Benjamin Davy, Sustainability Director, Teads
As the digital advertising ecosystem assumes a more proactive approach to the environmental impact of digital media campaigns, stakeholders are on the hunt for quick wins – actions that can be implemented to reduce the carbon footprint of media buys without disrupting business operations or incurring additional cost. One of the areas where the ecosystem has identified potential for optimisation is ad delivery, i.e., the transfer of ad-related files to the end user. Advertisers have invested in services centred around compressing image and video assets more efficiently, with the dual purpose of reducing load on networking resources and improving performance.
Reducing the file size of ads is a seemingly simple and straightforward optimisation: we might think that it costs practically nothing to compress files more aggressively, no complicated tech like custom carbon-aware bidding algorithms is required, and the idea that reducing the volume of data traveling through networks leads to networks using less energy is relatively intuitive. However, once we consider questions like how creative assets are handled until they reach the user consuming the ad, and how the internet’s emissions are quantified, doubt may be cast on the idea that small reductions in ad payloads lead directly to energy savings.
The emissions associated with transferring ad payloads through networks can often represent a material component of a campaign’s total environmental footprint. This point is well-illustrated by the following campaign example, whose emissions are quantified using a basic application of the latest proposed methodology for digital ad emissions, developed by IAB Europe’s Methodology & Framework Working Group. Using some demo data to represent a programmatic video campaign in the UK, we observe that the level of emissions estimated for ad delivery makes up almost a quarter of the total estimated campaign emissions, excluding production.
The level of impact will vary with the ratio of users on fixed and mobile connections, respectively, as these have a different carbon intensity as surfaced by the lifecycle assessments referenced in the methodology. Similarly, the estimated impact is a function of the transfer payload – this is the relationship that leads to claims around lighter files and a lower carbon footprint. Indicatively, the electricity consumption associated with transferring a given payload over a mobile connection is more than 10 times larger than the respective figure for fixed connections. In the example above, delivery emissions were estimated by assuming that the average payload for each ad was about 2.5 MB. An average ad payload reduction of half a megabyte would result in a 20% reduction in the estimated emissions. Is this reduction on paper associated with a real, tangible reduction in carbon footprint?
A short refresher on carbon accounting is required to answer this question. When quantifying the emissions of a system, whether that be an electricity grid, water grid, or information grid, in this case, different approaches can be followed. Oftentimes, the total inventory of emissions is divided by the total volume of goods or services provided, which is called an attributional approach (e.g., kilograms of CO2e per kWh of electricity consumed in a year). These attributional carbon intensities are quite useful as they provide an easy way to gauge the emissions that each unit of a good or service is associated with. On the flip side, they do not reflect the consequences of the level at which a good or service is demanded. They are not meant to quantify carbon emissions comparatively and may therefore fail to provide meaningful figures in cases where optimisations are being evaluated. Concretely, for our use case, a lower file size will be attributed a lower share of the total emissions that were estimated at a certain point in time for the network infrastructure.
From a carbon footprint standpoint, systems are often less or more responsive to changes in demand than these figures would suggest, depending on factors such as load. A water grid is a useful non-digital example here: energy is required continuously to maintain pressure in the pipes and ensure the system is ready to respond to households’ demand for water. The system’s energy draw may still increase under load, but a significant portion of its emissions will result from the overhead required to keep the system running and delivering. Using an attributional carbon intensity, calculated by dividing total emissions by total volume of water, would overrepresent the impact of consuming less water and underrepresent this overhead.
It's a similar story with networks and digital infrastructure: baseline energy consumption is high and idle capacity is considerable, meaning that small changes in payloads may not result in direct energy savings. In simple words, and to maintain the analogy, more energy is required to keep the internet’s pipelines flowing rather than to transfer any specific piece of information. It is worth noting that cellular networks are more power proportional to traffic, especially with the rise of energy-saving techniques.
The internet also happens to be incredibly chaotic, adding another layer of uncertainty. Quoting one of the papers on network electricity consumption reviewed by the Methodology & Framework Working Group, “a core design principle of the internet is that it is operational 24/7 and resilient to failure, so each packet may take a completely different route over entirely independent networks.” Since it is impossible to precisely predict the route the data will take during transfer, the same applies to the carbon footprint of this transfer.
The points above do not mean that reducing the payload of ads is a futile exercise. In the long term, lower cumulative demand for digital infrastructure may lead to less capacity expansion and therefore have an indirect impact on the system’s total emissions. However, claims of carbon footprint reductions in the short term should be checked for responsible use of references and a clear causal link between the technology or optimisation being used and the reduction in impact.
IAB Europe has explored image and video asset compression in collaboration with members and other industry bodies in the Sustainable Creatives Task Force. Through a survey, research, and testing, the Task Force collected insights into how the digital ad ecosystem compresses files, what’s defined in industry guidance and requirements, and which actions are suggested as best practice. Behind this work is the hypothesis that more efficient compression and delivery can yield both lower load on IT infrastructure and improvements in ads’ performance. Apart from potentially reducing energy consumption, lighter ad files also load faster – a difference that can be perceivable and affect user behavior. Multiple examples of faster loading leading to improved KPIs were covered in the IAB Europe webinar held to showcase the Task Force’s work, and the focus is now on testing the hypothesis above in a live campaign environment.
As such, there may be enough (more traditional) upside to drive further work in this area beyond the current incentive of showcasing corporate responsibility and leadership on digital emissions. Multiple companies in the digital ad ecosystem are focused on developing technologies that lead to better ad outcomes via improvements in user experience. Beyond reducing ad payload, many implement practices such as lazy loading to deliver ads with both better performance and potentially lower emissions. Furthermore, advancements in adaptive streaming technologies allow for the dynamic adjustment of video quality and delivery based on network conditions and user viewing behavior, ensuring a smoother user experience while potentially minimising unnecessary data transfer.
The second main question to consider in relation to the carbon footprint of ad delivery is which of the stakeholders involved in a digital ad campaign actually control the compression of creative assets. Before they reach end users, the assets that make up digital ads are likely to have undergone multiple rounds of compression. Original video files may be shot in raw camera formats and then compressed to an intermediate codec in post-production before being compressed further to arrive at a master file – the version that is uploaded to an ad server (referring to any hosting service for ads, in-house or third-party). Usually, the master file is also subject to requirements and guidelines issued by the ad server. From there, the ad server is likely to create multiple transcodes from this master file to serve in different environments (e.g., based on bandwidth or compatibility), with the logic depending on factors such as how many times the ad is likely to be served.
The ultimate dimensions of the creative assets delivered to end users are primarily determined by the transcoding processes implemented by each ad server, based on the master file provided. While certain advanced configurations may afford advertisers greater control over these transcoding parameters, in the absence of such granular control, additional compression applied to the master file prior to upload does not guarantee a directly proportional reduction in the file size of the resulting transcoded assets. Indeed, the final file sizes and, consequently, the campaign's network resource utilisation during delivery, are contingent upon the specific transcoding algorithms employed by each ad server.
Furthermore, applying compression to the master file beyond the levels recommended by a given ad server's specifications can potentially diminish the overall efficiency of the platform's optimisation process. If excessive data reduction is performed prior to upload, it may impede the ad server's ability to effectively transcode and optimise the asset for various delivery scenarios, potentially leading to sub-optimal file sizes.
The environmental impacts of data transfer are not directly proportional to traffic. This means smaller file sizes don't always translate to a measurable carbon reduction from a technical standpoint.
However:
Environmental impact assessment methodologies have limitations. Attributional assessments can suggest impact reductions on paper, but these should be interpreted cautiously. Still, they offer a useful incentive to adopt best practices with long-term benefits.
Although the immediate technical impact of reducing file sizes may be small, widespread, consistent improvements across the digital value chain can influence future infrastructure decisions and support a more sustainable ecosystem. Progress depends on collective effort and a shared commitment to responsible digital design.
For more information on IAB Europe’s Sustainability Standards work and how you can get involved, please visit our Sustainability Hub here or contact Dimitis Beis at beis [at] iabeurope.eu.
With Interact 2025 just over a week away, we’re continuing to shine a spotlight on some of the must-attend sessions from this year’s agenda. This time we’re turning our attention to Policy.
Taking place on 20th-21st May 2025 at nHow Brussels in Belgium, Interact is the conference that brings leaders from across the digital advertising ecosystem together, all under one roof. With a central theme of ‘Digital Skylight – Clarity and Purpose for 2025 and Beyond’, this year’s event will explore how our industry can navigate a fast-changing landscape shaped by economic uncertainty, regulatory shifts, and technological advancements.
Find out more about the event here, and discover what to expect on the topic of Policy at the event below.
Afternoon Masterclass - Regulatory Framework on Digital Advertising: Balancing Privacy and Innovation
Joining the afternoon masterclass agenda, our deep-dive policy session will explore one of the most urgent questions facing our industry - how can we uphold user privacy while enabling the innovation and growth needed to keep Europe competitive?
Moderated by Daphne Van Doorn, Head of EU Affairs at BVDW, the session will bring together a powerhouse panel of experts from across the ecosystem:
Max Schrems, Founder, NOYB
Chris Hydak, Assistant General Counsel, Privacy and Regulatory Affairs, Microsoft
Dr. Sachiko Scheuing, European Privacy & AI Governance Officer, Acxiom
Miguel Valle del Olmo, Attaché for Digital Matters, Spanish Permanent Representation to the EU
This discussion comes at a pivotal time. The European Commission’s 2025 work programme signals a renewed focus on regulatory simplification aimed at boosting European competitiveness. With the withdrawal of the draft ePrivacy Regulation and the upcoming Digital Fairness Act, alongside efforts to streamline and potentially consolidate the digital acquis under a new European Data Union Strategy, the future direction of privacy and digital advertising regulation is once again in the spotlight.
Plus, the Commission has announced plans for a targeted reform of the GDPR, scheduled for 21st May - the very date of our session.
Key topics up for debate will include:
This session is just one of many insightful discussions happening at Interact 2025, with expert voices from across the digital advertising ecosystem coming together to dive into and debate some of the hottest topics of today.
Don’t Miss Interact 2025
Interact 2025 isn’t just about those in-depth sessions; it’s also the place to connect, collaborate, and build the future together. With a packed agenda that also includes the release of the AdEx Benchmark Results, deep-dive discussions, and evening networking events, this is an event not to be missed.
Don’t Miss Out on Our Limited Time Offer for 20% Off:
Use code iab20eu at checkout and get 20% off your ticket – offer valid for a short time only!
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