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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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.

Study reveals that brands with more mature identity programs were significantly more likely to be successful in achieving their key objectives Tapad, a part of Experian, a global leader in cross-device digital identity resolution and a part of Experian, has commissioned Forrester Consulting, part of a leading research and advisory firm, to conduct a new study that evaluates the current state of customer data-driven marketing and explores how marketers can use identity solutions to deliver privacy safe and engaging experiences, in an evolving data landscape. The study highlights the changing ground rules for digital marketing and the threat that poses to marketers’ ability to deliver against long standing KPIs and campaign goals. Nearly two-thirds (62%) of respondents said that the forces of data deprecation will have a significant (40%) or critical (21%) impact on their marketing strategies over the next two years. Among those surveyed, identity resolution strategies have surfaced as an opportunity to create more powerful customer experiences, with 66% aiming to have it help improve customer trust and implement more ethical data collection and use practices, while nearly 60% believe it will point the way to more effective personalization and data management practices. Although organizations are eager to implement identity resolution strategies, a complex web of solutions and partners makes execution a challenge. For example, respondents report using at least eight identity solutions on average, across nearly six vendor partners, and they expect that fragmentation to persist in the ‘cookieless’ future. Additionally, brands’ identity resolution technologies typically represent a patchwork of homegrown and commercial solutions. Eighty-one percent of respondents use both in-house and commercial identity resolution tools today, and 47% use a near-equal blend of the two. Despite the challenges, many brands have the foundation for a strong identity resolution strategy in place, and they are thriving as a result. Specifically, more mature brands were 79% more successful at improving privacy safeguards to reduce regulatory and compliance risk, 247% more successful at improving marketing ROI, and over four times more effective at improving customer trust compared to their low-maturity peers. Additional insights include: Marketers Are Increasingly Playing a Key Strategic Role Within the Organization, But There is a Mandate to Demonstrate Value. Nearly three-quarters of respondents in our study agree the marketing function is more strategically important to their organization than it used to be, while almost two-thirds agree there’s more pressure than ever to prove the ROI or business performance of their activities. Consumers Expect Brands to Deliver Engaging Experiences Across Highly Fragmented Journeys: Tapad, a part of Experian found that 72% of respondents agree that customers demand more relevant, personalized experiences at the time and place of their choosing. At the same time, 67% of respondents recognize that customer purchase journeys take place over more touchpoints and channels than ever, and 59% of respondents agree that those journeys are less predictable and linear than they once were. Marketing Runs on Data, But the Rules Governing Customer Data Usage are Ever-Evolving: According to the study, 70% of decision-makers agree that consumer data is the lifeblood of their marketing strategies – fueling the personalized, omnichannel experiences customers demand. At the same time, 69% of respondents recognize that customers are increasingly aware of how their data is being used. At least two-thirds agree that data deprecation, including tighter restrictions on data use (66%), as well as operating system and browser changes impacting third-party cookies (68%) means that legacy marketing strategies are unlikely to remain viable in the long-term.“ Our latest survey findings give us a better understanding of how our customers and other companies around the world are trying to master the relationship between people, their data and their devices,” said Mark Connon, General Manager at Tapad, a part of Experian. “This research shows why it's fundamental for the industry to continuously work to develop solutions that are agnostic. Tapad, a part of Experian has worked tirelessly to deliver on this with our Tapad Graph, and by introducing solutions like Switchboard to help the evolving ecosystem and in turn helping customers reap the benefits of better identity in both short and long-term.” The study is founded on an online survey of over 300 decision-makers at global brands and agencies, which was fielded from March to April, 2021. Data deprecation and identity are fast-developing, moving targets, so this study delivers targeted insights and recommendations for how to prepare for coming shifts in customer data strategies – whether they manifest tomorrow or a year from now. Get started with The Tapad Graph For personalized consultation on the value and benefits of The Tapad Graph for your business, email Sales@tapad.com today!

Marketers are always challenged to expand sales beyond “business as usual,” while being good stewards of company resources spent on marketing. Every additional dollar spent on marketing is expected to yield incremental earnings—or else that dollar is better spent elsewhere. You must be able to determine return on advertising spend (ROAS) for any campaign or platform you add to your marketing mix. A key driver of positive ROAS is incremental customer actions produced by ad exposure. Confident, accurate measurement of incremental actions is the goal of an effective testing program. Why do we test campaign performance? Because demonstrating incremental actions from a campaign is a victory. You can keep winning by doing more of the same. Not finding sufficient incremental actions is an opportunity to reallocate resources and consider new tactics. Uncertainty whether the campaign produced incremental actions is frustrating. Ending a profitable marketing program because incremental actions were not effectively measured is tragic. Test for success When you apply rigorous methods to test the performance of campaigns, you can learn to make incremental improvements in campaign performance. The design of a marketing test requires the following: Customer Action to be measured during the test. This action indicates a recognizable step on the path to purchase: awareness, evaluation, inquiry, comparison of offers or products, or a purchase. Treatment, i.e., exposure to a brand’s ad during a campaign. Prediction regarding the relationship between action and treatment (e.g., Ad exposure produces an increase in purchase likelihood). Experimental design is the structure you will create within your marketing campaign to carry out the test. Review of results and insights. Selecting a customer action to measure Make sure that the customer action you measure in your test is: Meaningful to the campaign’s goal. What is the primary goal of the campaign? Is it brand awareness? Web site visits? Inquiries? Completed sales? An engagement by the customer. Your measurement should capture meaningful, deliberate interaction of consumers with the brand. Attributable to advertising. There should be a reasonable expectation that ad exposure should increase, or perhaps influence the nature of customer actions. Abundant in the data. Customer action should be a) plentiful and b) have a high probability of being recorded during the ad campaign (in other words, a high match rate between actions and the audience members). Selecting campaign treatments It is best for treatments to be as specific as possible. Ad exposures should be comparable with respect to: brand and offer, messaging, call to action, and format. Making a prediction This is the “hypothesis.” Generally, you assume that exposure to advertising will influence customer actions. To do this, you need to reject the conclusion that exposure does NOT affect actions (the “null hypothesis”). Elements of an experimental design An attribution method that links each audience to their purchase action during the test. This consists of a unique identifier of the prospect which can be recognized both in records of the audience and records of the measured action during the measurement period. A target audience that receives ad exposure. A control audience that does not receive ad exposure. It provides a crucial baseline measurement of action against which the target audience is compared. Time boundaries for measurement, related to the treatment: Pre-campaign Campaign Post-campaign Randomly selected audiences (recommended) Some audience platforms, such as direct mail and addressable television operators, feature the ability to select distinct audience members in advance. Randomly selected audiences can generally be assumed to be similar in all respects except ad exposure. The lift of the action rate is simple to calculate: Campaign Lift = (Action Rate (target) / Action Rate (control)) -1 Non-randomly selected audiences are more difficult, but still possible, to measure effectively. There may be inherent biases between them that may or may not be obvious. To measure campaign performance, we must first account for any pre-existing differences in customer actions, and then adjust for these when measuring the effect of ad exposure. Typically, the pre-campaign period (and possibly the post-campaign period as well) are used to obtain a baseline comparison of actions between the two audiences. This is a “difference of differences” measurement: Baseline lift = (Action Rate (target) / Action Rate (control)) -1 Campaign Lift = (Action Rate (target) / Action Rate (control)) -1 Net campaign lift (advertising effect) = Campaign Lift – Baseline Lift Analyzing results and insights How large is the lift? This is generally expressed as a percentage increase in action rate for the target audience vs. the control audience. Are we confident that the lift is real, and not just random noise in the data? This question is answered with the “confidence level.”. 95% confidence means the probability of a “true positive” result is 95%; and the probability of a “false positive” due to random error is 5%. What was the campaign cost per incremental action? If you also know the expected revenue from each incremental action, you can project out incremental revenue, from which you can calculate return on ad spend. Other insights: Do the results make directional sense (we would hope that ad exposure will cause an increase in customer actions, not a decrease)? Does action rate generally increase with the number of ad exposures? Summary Well-designed testing and measurement practices allow you to learn from individual advertising campaigns to improve decision-making. The ability to draw confident conclusions from campaigns will allow experimentation with different strategies, tactics, and communication channels to maximize performance. These test-and-learn strategies also enhance your ability to adjust to marketplace trends by monitoring campaign performance. To learn how Experian’s solutions can help you measure the success of your marketing campaigns, watch our short video, or explore our measurement solutions.