Cookie Syncing: What Is It and How Does It Work?

145 Comments / Privacy / By Content Team

If you work in online advertising, then you’ve probably heard of cookie syncing. But what is it? How does it work? And why do AdTech and data companies use it? Here we’ll try to answer those very questions, and many more! You can first start by watching this short video to get an overview of what cookie syncing is and how it works, and then read the rest of the post below to learn more.

What is Cookie Syncing and how does it work?

Cookie syncing, also known as cookie synchronization or cookie matching, is a technique used in digital advertising to share user data between different advertising technology platforms. It helps advertisers and marketers create a more comprehensive profile of a user’s online behavior and interests across multiple websites and platforms. This shared data allows them to deliver more targeted and relevant advertisements to users.

Cookie-syncing is a process that enables the adtech partners (SSPs, DMPs, CDPs, and DSPs) to synchronize their cookies and share the incorporated user’s data from different websites with each other. As a result, the DSPs can know about the user (interests, demographics, location, etc.) and return the bid response with the right bid and relevant ad creative.

How Does Cookie Syncing Work?

Cookie syncing works when two different advertising systems (aka platforms) map each other’s unique IDs and subsequently share information that they have both gathered about the same user.

But how do they collect information about users in the first place?

Well, it all starts with the browser. Each time a user visits a website that contains ads (or third-party tracking tags), the browser sends an ad request to an advertising technology platform (e.g. a DSP). The DSP then creates a unique user ID, if one doesn’t exist already, and stores that ID in a cookie.

It’s important to note here that it is a third-party cookie because the ad request is made to an AdTech platform’s domain, not the domain of the website the user is visiting. Within this ad request, the DSP also calls a pixel URL supplied by a different advertising technology platform (e.g. a DMP). The DSP includes its user ID, which it created for that user, as a parameter in the pixel URL call.

Importance of Cookie-Syncing in Digital Advertising?

Cookie-syncing plays a pivotal role in the intricate landscape of digital advertising, acting as the silent conductor that orchestrates the harmonious symphony of targeted marketing strategies. At its core, cookie-syncing facilitates the seamless exchange of information between different ad tech platforms, enabling them to synchronize their user tracking mechanisms and align their efforts in crafting a tailored user experience.

In the realm of programmatic advertising, where RTB and personalized content delivery are the norm, cookie-syncing emerges as the linchpin that binds various stakeholders together. Advertisers, publishers, and ad exchanges all rely on this process to establish a unified understanding of user behaviors, preferences, and interactions.

The impact of cookie-syncing extends beyond mere data sharing; it fuels the engine of precision targeting. Advertisers leverage the insights gleaned from this synchronization to fine-tune their campaigns, ensuring that the right message reaches the right audience at the right moment. This synergy enhances the user experience, as individuals are presented with advertisements that resonate with their interests and needs, fostering a sense of relevance rather than intrusion.

Benefits of Cookie-Syncing

Cookie-syncing, a fundamental process in the realm of digital advertising, offers a myriad of benefits that contribute to the effectiveness and efficiency of targeted marketing efforts. These advantages highlight the pivotal role that cookie-syncing plays in maximizing ad campaign performance and enhancing the user experience:

Enhanced Targeting Precision: Cookie-syncing enables advertisers to combine insights from multiple platforms, allowing for a more comprehensive understanding of user behavior and preferences. This comprehensive view empowers advertisers to create highly refined and accurate audience segments, leading to more precise targeting and personalized ad delivery.

Reduced Ad Wastage: With cookie-syncing, ad exchanges and demand-side platforms (DSPs) can synchronize user data, avoiding redundant or overlapping ad impressions. This reduces ad wastage, as advertisers can avoid bombarding users with the same or irrelevant ads, thereby conserving ad budgets and optimizing the allocation of resources.

Seamless Cross-Device Tracking: In today’s multi-device world, users often switch between smartphones, tablets, and computers. Cookie-syncing enables the creation of cohesive user profiles that span across devices, ensuring a seamless and consistent advertising experience. Advertisers can better understand user interactions across different touchpoints, delivering more relevant and engaging content.

Improved User Experience: By utilizing cookie-syncing to deliver personalized and contextually relevant ads, advertisers can enhance the overall user experience. When users are presented with ads that align with their interests and preferences, they are more likely to engage positively with the content, leading to higher click-through rates and conversion rates.

Data Enrichment and Insights: Cookie-syncing allows for the enrichment of user profiles with data from various sources, enabling deeper insights into user behaviors and preferences. This enriched data can be used to refine audience segments, create more compelling ad creatives, and make data-driven decisions to optimize campaign performance.

Collaborative Advertising Ecosystem: Cookie-syncing fosters collaboration and partnerships within the advertising ecosystem. Advertisers, publishers, ad exchanges, and other stakeholders can share data and insights more effectively, facilitating a more cohesive and interconnected advertising landscape.

Re-targeting: It is almost impossible to re-target the users without cookie-syncing. The process enables the advertisers to drop a cookie in the user’s browser when they first visit the product page. As the user visits your website or any other website, the advertiser leverages cookie-syncing to identify the same user and serve the right ad.

Disadvantages of Cookie-Syncing

While cookie-syncing offers numerous benefits to the digital advertising ecosystem, it also comes with certain disadvantages and challenges that advertisers and users should be aware of:

Privacy Concerns for cookie Syncing: Cookie-syncing involves the sharing and synchronization of user data across different platforms, which can raise privacy concerns. Users may be uncomfortable with the idea of their data being shared between multiple entities without their explicit consent. This can lead to potential breaches of user privacy and result in negative perceptions of brands that engage in extensive data sharing.

Data Security Risks: The more entities involved in cookie-syncing, the greater the potential for data breaches or unauthorized access. Advertisers must implement robust security measures to safeguard user information and ensure that data transfers are conducted securely.

Ad-Blocking and Tracking Prevention: Many users employ ad-blockers or tracking prevention mechanisms to limit data collection and personalized ads. These tools can disrupt cookie-syncing efforts and hinder the effectiveness of targeted advertising campaigns.

Legal and Regulatory Challenges: The sharing of user data across platforms through cookie-syncing must adhere to privacy regulations such as GDPR, CCPA, and other regional data protection laws. Advertisers must ensure proper compliance, which can be complex and may require ongoing monitoring and adjustments to stay in line with evolving regulations.

Technical Complexities: Cookie-syncing involves technical integration between different ad tech platforms, which can be complex and require ongoing maintenance. Technical issues or compatibility challenges between platforms can disrupt the synchronization process and impact campaign performance.

Adoption Barriers: Smaller or less technically advanced advertisers or publishers may face challenges in implementing and managing cookie-syncing effectively. This could lead to a potential imbalance in the advertising landscape, favoring larger players with the resources and expertise to navigate the complexities.

Alternatives To Cookies For Marketers

Certainly, as the digital landscape evolves and privacy concerns become more prominent, various alternatives to traditional web cookies have been explored or developed. Here are some other options for web cookies:

Contextual Advertising: Contextual advertising involves displaying ads based on the content of the webpage being viewed. By analyzing keywords, topics, and themes on the page, marketers can serve relevant ads to users without relying on user-specific tracking.

First-Party Data: Leveraging first-party data collected directly from user interactions on your website can be highly valuable. This data can include user preferences, behavior, purchase history, and more. It allows for personalization while maintaining user privacy.

Behavioral Segmentation: Instead of tracking individual users, marketers can group users into segments based on similar behaviors and interests. This approach provides a level of personalization without relying on tracking specific users across sites.

Federated Learning of Cohorts (FLoC): Developed by Google, FLoC groups users into cohorts based on their browsing behavior. Advertisers can target these cohorts, which consist of users with similar interests, without directly identifying individuals.

Server-Side Tracking and Analytics: Conducting tracking and analytics on the server side rather than the client side can provide valuable insights without the need for individual user tracking. This approach can enhance data privacy.

Permission-Based Marketing: Obtain user consent for data usage and personalized marketing. This not only respects user privacy but also builds trust, as users are aware and in control of how their data is used.

Customer Relationship Management (CRM) Data: Utilize data from your CRM system to personalize marketing efforts. CRM data includes information that users willingly provide, enabling tailored campaigns based on their preferences and interactions with your brand.

Predictive Analytics: By analyzing historical data and patterns, marketers can make predictions about user behavior and preferences. This approach can provide insights into what products or services a user might be interested in.

Location-Based Marketing: Utilize geolocation data to deliver targeted messages and offers to users based on their physical location. This can be effective for local businesses and events.

Content Personalization: Focus on delivering personalized content and experiences based on user interests and preferences, as indicated by their on-site behavior.

Cross-Device Tracking with Consent: If users provide consent, implement cross-device tracking mechanisms that link user behavior across devices for a more coherent understanding of their journey.

Blockchain-Based Solutions: Explore blockchain technology to ensure secure and transparent user data management. Users can control their data more while benefiting from personalized experiences.

Local Storage: Browsers allow websites to store data locally on a user’s device using technologies like HTML5 Local Storage. While this doesn’t offer the same cross-site tracking capabilities as cookies, it can be used for storing small amounts of data for a specific website’s use.

Session Storage: Similar to local storage, session storage allows data to be stored temporarily for a single browsing session. Once the user closes the browser or tab, the data is deleted.

IndexedDB: IndexedDB is a low-level API for storing large amounts of structured data in a user’s browser. It can be used to store data for offline use or for specific website functionality.

Browser Fingerprinting: This involves collecting a range of information from a user’s browser, such as user-agent string, screen resolution, installed fonts, and more, to create a unique “fingerprint” for that user. While this technique can be used for tracking, it also raises privacy concerns.

Cookie uses policies around the World

Various countries and regions around the world have implemented different cookie policies and regulations to address user privacy and data protection concerns. Keep in mind that these regulations might have evolved or changed since then. Here are some notable cookie policies in different parts of the world:

European Union (EU): The EU’s General Data Protection Regulation (GDPR) has significant implications for cookies and online tracking. It requires websites to obtain clear and informed consent from users before placing non-essential cookies. Users must have the option to opt out of cookies, and consent should be specific to each purpose of data processing. Websites must also provide clear information about the types of cookies used and their purposes.

United Kingdom (UK): The UK’s implementation of GDPR, known as the UK GDPR, largely aligns with the EU GDPR in terms of cookie policies. The Information Commissioner’s Office (ICO) in the UK provides guidance on obtaining valid consent for cookies and similar technologies.

California, USA: The California Consumer Privacy Act (CCPA) requires websites to inform users about the types of personal information collected, including through cookies, and the purposes for which it will be used. Websites must provide an option for users to opt out of the sale of their personal information, which may include data collected via cookies.

Brazil: Brazil’s General Data Protection Law (LGPD) mandates that websites and online platforms must obtain explicit consent from users before collecting and processing their personal data, which includes data collected through cookies. Users must be provided with clear and comprehensive information about the data collection and processing activities.

Canada: Canada’s Personal Information Protection and Electronic Documents Act (PIPEDA) includes guidelines for online tracking and the use of cookies. Websites must inform users about the purpose of data collection, provide options to opt out, and obtain consent for non-essential cookies.

Australia: Australia’s Privacy Act includes provisions related to cookies and online tracking. Websites are required to inform users about the collection of personal information through cookies and provide options to manage their preferences.

Japan: Japan’s Act on the Protection of Personal Information (APPI) requires websites to inform users about the purpose of data collection, obtain consent for the use of cookies, and provide options for users to withdraw their consent.

South Korea: South Korea’s Personal Information Protection Act (PIPA) requires websites to obtain user consent for the collection and use of personal information, which includes data collected through cookies.

India: India has finally passed a comprehensive data protection law – the Digital Personal Data Protection Act, 2023 (“DPDP Act”). While the DPDP Act replicates many aspects of the EU GDPR, it diverges on a number of important points reflecting both learnings from the operation of the EU GDPR and the need to apply data protection laws within an Indian context.

Cookie syncing is a powerful tool in the digital advertising toolbox, enabling precise targeting, optimizing campaigns, and enhancing user experiences. However, it must navigate challenges related to privacy, security, and technical complexities. The future of cookie syncing lies in adapting to evolving privacy regulations, embracing emerging technologies, and prioritizing user consent and data protection.