In 2022, Google began changing the availability of the information available in User-Agent strings across their Chromium browsers. The change is to use the set of HTTP request header fields called Client Hints. Through this process, a server can request, and if approved by the client, receive information that would have been previously freely available in the User-Agent string. This change is likely to have an impact on publishers across the open web that may use User-Agent information today.
To explain what this change means, how it will impact the AdTech industry, and what you can do to prepare, we spoke with Nate West, our Director of Product.
What is the difference between User-Agents and Client Hints?
A User-Agent (UA) is a string, or line of text, that identifies information about a web server’s browser and operating system. For example, it can indicate if a device is on Safari on a Mac or Chrome on Windows.
Here is an example UA string from a Mac laptop running Chrome:

To limit the passive fingerprinting of users, Google is reducing components of the UA strings in their Chromium browsers and introducing Client Hints. When there is a trusted relationship between first-party domain owners and third-party servers, Client Hints can be used to share the same data.
This transition began in early 2022 with bigger expected changes beginning in February 2023. You can see in the above example, Chrome/109.0.0.0, where browser version information is already no longer available from the UA string on this desktop Chrome browser.
How can you use User-Agent device attributes today?
UA string information can be used for a variety of reasons. It is a component in web servers that has been available for decades. In the AdTech space, it can be used in various ad targeting use cases. It can be used by publishers to better understand their audience. The shift to limit access and information shared is to prevent nefarious usage of the data.
What are the benefits of Client Hints?
By using Client Hints, a domain owner, or publisher, can manage access to data activity that occurs on their web properties. Having that control may be advantageous. The format of the information shared is also cleaner than parsing a string from User-Agents. Although, given that Client Hints are not the norm across all browsers, a long-term solution may be needed to manage UA strings and Client Hints.
An advantage of capturing and sharing Client Hint information is to be prepared and understand if there is any impact to your systems and processes. This will help with the currently planned transition by Google, but also should the full UA string become further restricted.
Who will be impacted by this change?
Publishers across the open web should lean in to understand this change and any potential impact to them. The programmatic ecosystem supporting real-time bidding (RTB) needs to continue pushing for adoption of OpenRTB 2.6, which supports the passing of client hint information in place of data from UA strings.
What is Google’s timeline for implementing Client Hints?

Do businesses have to implement Client Hints? What happens if they don’t?
Not capturing and sharing with trusted partners can impact capabilities in place today. Given Chromium browsers account for a sizable portion of web traffic, the impact will vary for each publisher and tech company in the ecosystem. I would assess how UA strings are in use today, where you may have security concerns or not, and look to get more information on how to maintain data sharing with trusted partners.
We can help you adopt Client Hints
Reach out to our Customer Success team at tapadcustomersuccess@experian.com to explore the best options to handle the User-Agent changes and implement Client Hints. As leaders in the AdTech space, we’re here to help you successfully make this transition. Together we can review the options available to put you and your team on the best path forward.
Get in touch
About our expert

Nate West, Director of Product
Nate West joined Experian in 2022 as the Director of Product for our identity graph. Nate focuses on making sure our partners maintain and grow identity resolution solutions today in an ever-changing future state. He has over a decade of experience working for media organizations and AdTech platforms.
Latest posts

Email hashing was originally intended to be used as an email security feature that has ended up being a very powerful marketing tool. A hashed email is a cryptographic function that changes an email address to a random code which can be used as an anonymous customer identifier. This code is privacy-safe and cannot be traced back to the customer’s email address. However, this hashed email can function like a digital passport that traces every behavior and action a customer takes when logged into an account that is authenticated with an email, making hashed emails a goldmine for customer data. Today emails are used across traditional publishers and within the CTV ecosystem; tying them to more consumer touch points than ever before. Why the emphasis now? Cookies are on their way out the door and have been the primary way that many marketers have tracked their existing and potential customers. In order to replace this granular level of data, marketers are likely going to need multiple solutions. With so many cookieless solutions and IDs appearing in the marketplace, the mapping of the customer journey is bound to be fragmented. Relying on first-party data, such as hashed email, is just one way to reduce that fragmentation; as it can serve as an authenticated starting point for cross-device identity resolution that can be leveraged for targeting, personalization and measurement. How can Tapad + Experian help? Tapad + Experian's Hashed Email Onboarding is a privacy-safe way to connect consumer email addresses to their related digital devices and other digital identifiers through high precision probabilistic identity. By onboarding hashed emails and incorporating them within your Tapad Graph file you can: Build a more holistic view of individuals and households and their relationship to email addresses in your first-party data set Leverage these relationships for increased cross-device scale for targeting Employ personalization tactics at the household or individual level across devices Create new audience segments and look-alike models for cross-channel activation Design more inclusive measurement and attribution for customer journey mapping Tapad, a part of Experian has built a hashed email onboarding product feature that works with the existing flexibility of The Tapad Graph to deliver the most holistic consumer view, combined with the attributes you need, in the structure that works best for your business objectives. Get in touch

The result of epic shifts from traditional cable to streaming television, the CTV ecosystem is experiencing compounded fragmentation, making it challenging for marketers to leverage in the most effective way for both activation and measurement. Heralded as the hot new household level device for highly engaged viewers, CTV brings massive opportunities for brands to move users down the funnel and incorporate CTV into their attribution modeling post-campaign. Leveraging CTV IDs within a cross-device identity resolution strategy can yield big benefits if you know how to do it right. Check out our breakdown of today’s CTV landscape to help you better understand how and what you can leverage for activation and measurement in the streaming-verse today. CTV Ecosystems as identifiers (for illustrative purposes only) This is just a small peak at the players and complexities of CTV IDs available for marketers today, but it illustrates the need to understand what IDs can benefit your strategies and where you can use them. Addressability and attribution Not all CTV devices and IDs are addressable; or have ad slots for biddable inventory for advertisers. For example, Apple TV devices and Apple TV + are not ad supported, but could still appear within an identity graph for measurement purposes; helping understand customer behavior and habits, which can inform marketing strategies. Having a household to individual view that's as inclusive as possible can provide valuable insights. CTV identity strategy Whether or not CTV devices or apps are addressable for advertisers, they can bring immense value when leveraged as part of a holistic identity resolution strategy. As a household level device with user authentication it can provide marketers a top-down view; unlocking household:individual targeting opportunities and unification of IDs at both levels for frequency management and customer journey mapping Get started with us Tapad, part of Experian, offers CTV ID onboarding and extension to our CTV ID Universe as a part of The Tapad Graph suite of products.

Third-party data has become the cornerstone to improve marketing effectiveness across all types of online and offline media. Consumer packaged goods (CPG) marketing faces a challenge when utilizing this data, as sales are often made through distributors such as grocery stores or mass merchandisers rather than directly to consumers. Without customer data files that can be enriched for insight, CPG companies often base marketing decisions on custom market positioning studies, surveys and generic consumer personas. These solutions can be quite expensive and prove difficult to develop a targeted marketing program. Optimize your CPG marketing strategy We have a team of experts that leverage the wealth of our database of thousands of attributes covering more than 300 million U.S. consumers and 130 million U.S. households—to identify the demographics and attitudes of a CPG target consumer using syndicated, mobile location, social media, and online behavioral data. We help connect various data points to provide CPG marketers with the ability to identify likely consumers, generate actionable marketing insight, and enable targeted advertising to these consumers that increases brand awareness and drives purchase behavior. Identifying likely consumers for consumer packaged goods To gain marketing insight about your customers, you need to identify consumers who are actively engaged with your brand, and compare them against non-engaged consumers, or consumers engaged with rival brands. Experian uses syndicated and digital actions data to identify these consumers and understand their characteristics. With digital actions data, we leverage search terms and landing pages relevant to your brand. We use our linking capabilities to identify the perfect target audience for your marketing initiatives. For example, we leveraged syndicated data that showed consumer preference for frozen meals based on household characteristics. This enabled our client to better understand the market size and attributes of its active consumers. Actionable CPG marketing insight Once marketers identify who their optimal target consumer is, they can begin to understand their ideal audience and compare it to consumers of competitive brands. This helps identify key demographics and psychographics that over-index to users of the brands compared to the population. As a result, you can gain a much better understanding of the demographics, life stage and lifestyle of your target consumer. We also help you to better inform your marketing communication and media and distribution strategies by identifying the channels your ideal audience is most likely to be found. Getting back to our example, consumers of frozen foods were found more likely to be females between the ages of 35-54 with busy families. They had multiple children in the home and participated in family activities, like zoos and fast-food dining. We were then able to identify the digital channels they were more actively engaged with and determine factors that influence their decision-making, such as product quality or consumer testimonials. By gaining insight into your target audience, you can create digital communication focused on specifics, like an active family looking for a quality meal. Turning insights into action by enabling targeted advertising With a better understanding of your target consumer, and the insight needed to catch their attention, you can unify your ideal target audience and serve advertising that builds brand awareness and increases conversion. Our Custom Analytics team uses advanced analytical techniques to create custom consumer personas. Our database of 130 million U.S. households is scored with a proprietary algorithm created specifically for your organization and creates audiences that are pushed to the preferred marketing channel of your target consumers. Leveraging our ConsumerView database, we can easily enable direct communication to your targeted consumers (such as our example that identified consumers of frozen food and their preferred channels) through direct mail, email, digital display, social media and mobile channels. We work directly with agencies to deploy an audience to a destination and can manage a campaign for our CPG clients. We can even help you determine campaign success by measuring campaign performance versus a relevant control, and profiles converters to help you see gains made in brand awareness to target consumers. These services give you the ability to test an advertisement directly to targeted consumers, measure the effectiveness of the advertisement, then plow back the learnings into future campaigns, enabling greater consumer brand awareness and conversion while managing marketing effectiveness. Experian is here to help We have worked extensively with a variety of CPG companies to improve marketing effectiveness and drive brand awareness. We can help your organization take your marketing campaigns to the next level. Our data assets and advanced analytics generate actionable insights that enable you to identify and communicate with consumers more effectively. For more information about how we can help your organization gain valuable insights to identify your ideal customers and the best channels to reach them, contact us. Get in touch