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.
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.
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In our upcoming 2011 Digital Marketer Report, we will cover what influences purchase decisions. While you'll have to wait to read the report to see the entire list, when ranking influencers to purchase decisions: 54% of U.S. adults identified old-fashioned Word of Mouth (WOM), while information from webpages (47%) ranked second and online consumer reviews (31%) ranked as the third most important. It's nearly impossible to measure old-fashioned WOM, and “Information from a website” is a very broad category. Gauging the uptake in online consumer reviews is another story, however. Visits to online review pure-play Yelp.com is a good proxy for the uptake in online reviews in the service sector (restaurants, dry cleaners and dentists to name a few). Over the past two years, visits to Yelp.com have increased over 136%. Given such impressive and steady growth since 2009, you might assume that Yelp and other sites like it have become ubiquitous. Your assumption, however, would be incorrect. While age demographics of visitors to the site show that use of the online consumer reviews has reached maturity (Internet users over the age of 55 make up the largest age bin at 25%), geo-demographics, or visits by DMA, tell a completely different story. The top five cities by representation; San Francisco, San Diego, Monterey, Los Angeles and Sacramento reveal the first skew, that Yelp.com visitors favor the West Coast, where the company was founded. So it seems that, by percentage, the largest U.S. cities also figure significant. When looking at visitors to the site by Mosaic™ segments, Americas Wealthiest, Young Cosmopolitans and other affluent types figure heavily in the site's traffic. Taken all together, the numbers reveal that while Yelp.com continues to grow, its participants continue to be a very distinct subset of U.S. Internet users. This niche set of users might explain why traditional WOM continues to show more significance in influencing purchase decisions. Want to learn more about other purchase decision influencers? Click here to request a copy of Experian Marketing Services highly-anticipated 2011 Digital Marketer Report, launching in late March. The report features an editorial by Bill Tancer as well as unreleased data spanning email, social, mobile, search and more.

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CBS reported that 48 million viewers watched at least some of the championship game. According to viewership data from Experian Simmons, men's tournament viewers outnumbered women's tournament viewers by a ratio of 3.7 to 1. That's nearly four men's tournament viewers for every viewer of the women's tournament. So who might be watching this year? Using Experian's Mosaic consumer lifestyle segmentation system combined with last year's tournament viewership data from Experian Simmons, we took a closer look. Men's Tournament Viewers Rise Above The Rim On Affluence The men's tournament draws a significant share of viewers from affluent households. Nearly half of viewers have household income of $75,000 or over. The ten most affluent Mosaic segments have an over-representation of men's tournament viewers compared to their corresponding share of U.S. adults. 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Brands and retail stores that have particular appeal to Dream Weavers include Nordstrom, Ralph Lauren, Nike, Eddie Bauer, Sephora, Dick's Sporting Goods and Banana Republic. But that's not to say that only affluent consumers are watching the men's tournament. Other segments with an above average concentration of men's tournament viewers include African-American Neighborhoods, Minority Metro Communities, America's Farmlands, and Young Cosmopolitans. Men's tournament viewers participate in a wide range of leisure and sport's activities (most notably golfing, football, softball, racquet sports, and weight training), have a preference for driving Cadillac, Acura, and Lexus automobiles, and have a high concentration of readers of such magazine titles as Golf Digest, Sports Illustrated, ESPN The Magazine, Barron's, and Black Enterprise. Women's Tournament Delivers Younger, More Ethnically Diverse Audience The audience for the women's tournament is decidedly different from the men's. About six out of every ten viewers have household income below $75,000. Mosaic segments with the greatest over-representation of women's tournament viewers include Struggling City Centers (young, single and single-parent minority renters living in low-income city neighborhoods throughout the South) and Minority Metro Communities (married couples and single-parent minorities with above-average incomes working in a mix of service industry and white-collar jobs). These two segments alone account for nearly 20% of the women's tournament viewing audience and contain about 2.5 times the concentration of viewers relative to their corresponding share of U.S. adults. Women's college basketball advertisers should note that the tournament delivers a less affluent audience compared to the men. Using Minority Metro Communities as an example, brands and retail stores that have particular appeal to this group and to the broader women's tournament audience overall include 7-Eleven, Ace Hardware, Hallmark, Sam's Club, Kmart, Dollar General, Big Lots, and Marshall's. Women's college basketball advertisers should note that the tournament delivers a less affluent audience compared to the men. Only four of the ten most affluent Mosaic segments have an over-representation of women's tournament viewers. When comparing a segment's share of the overall women's tournament viewing audience to its corresponding share of the men's tournament viewing audience, three of these four segments account for a higher share of women's viewers. These are America's Wealthiest, White Collar Suburbia, and Affluent Urban Professionals. Advertisers will be pleased to know that interest in the tournament from these segments helps lift the viewing audience into a higher income demographic. Using White Collar Suburbia as an example, retail stores that have particular appeal to this segment of the population include Brooks Brothers, Costco, Gap, J. Crew, Kohl's, Lord & Taylor, and Victoria's Secret. Other segments that contain a significantly higher share of women's viewers compared to men include Small-city Endeavors (a mix of lower income singles, families, and single parents living in older homes and small apartments in working class towns) and Professional Urbanites (upper-middle-class empty nesting couples and older singles in metropolitan areas). Men’s Tournament Viewers Compared to Women’s Tournament Viewers Men’s Tournament Top Ten Most Affluent Mosaic Segments Women’s Tournament America’s Wealthiest Dream Weavers White Collar Suburbia Upscale Suburbanites Enterprising Couples Small-town Success New Suburbia Families Status-conscious Consumers Affluent Urban Professionals Urban Commuter Families = Index of 100 to 125 = Index of 126 to 150 = Index above 150 The index shows the concentration of viewers for the men's and women's tournament for a segment compared to the segment's share of U.S. adults. For example, an index above 150 means that adults from the segment are 50% more likely to watch the tournament compared to U.S. adults overall.

Along with death and taxes, the third certainty as an online marketer is change. When we combine the rapid rate of online innovation with consumers' relentless pursuit of finding the best possible price, a pursuit that kicks into overdrive with economic uncertainty, it's critical to anticipate changes in consumer behavior and the adoption of new buying modalities. Here are three things that you should know about the group coupon phenomenon. By now, most of us are aware of Groupon, the privately held Chicago group couponing-company that rejected Google's $6 billion dollar acquisition offer in late 2010. Since it's founding in 2009, Groupon has grown to over 5 million visits per week to take the #25 spot in the Experian Hitwise Shopping & Classifieds category1 for the week ending January 29, 2011. But is Groupon, or more generally the category of online group buying, a fad or a significant change in the way we buy online? Here are three things that you should know about the group coupon phenomenon. Group Buying Has Reached Mainstream Adoption If you think that this new social buying trend is fueled by early adopters of technology, the young and hip technocrats, you may have been correct in January 2010. Today, you would be completely off the mark. According to Experian Hitwise for the four weeks ending January 29, 2011, the largest age-bin for visitors to Groupon.com are those Internet users over the age of 55 (37.5%). There is Applicability to Local and National Retailers While group coupons were heralded as the perfect solution for local online commerce, successful deals with national retailers (both bricks-and-mortar such as GAP and online pure-plays like Amazon.com) indicate that this movement will take its place alongside email and search as a key channel for marketers to consider. On January 19, 2011, LivingSocial.com, a Groupon competitor, offered a $20 Amazon credit for $10 (it should be noted that Amazon invested $175 million in LivingSocial.com). According to PC Magazine, over 1.3 million certificates were sold at a rate of over 100,000 per hour. The Race to Dominate the Space is Heating Up LivingSocial's Amazon play did more than just put up impressive numbers; it was a clear sign that the site is a viable threat to category leader, Groupon. According to Groupon CEO Andrew Mason, Groupon has over 500 competitors in the marketplace and growing. Have you considered group buying for your business? Along with anticipating this trend, with the growing number of competitors and offers you should think one step ahead – will consumers succumb to daily deal fatigue? Want to learn more about digital marketing in 2011? Click here to request a copy of Experian Marketing Services highly-anticipated 2011 Digital Marketer Report, launching in late March. The report features an editorial by Bill Tancer as well as unreleased data spanning email, social, mobile, search and more. ——— 1 Shopping and Classifieds Category: 28,586 top sites that specialize in online shopping, auctions and classifieds