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Google Chrome Removes 3rd Party Cookies | Implications for Digital Marketers


What Are 3rd Party Cookies?

3rd party cookies are cookies that are created by a different website or domain than the current website you’re browsing. Online advertisers commonly use 3rd party cookies to track users’ activity across various websites. This information provides more insight into users’ tendencies and behaviors, which in turn helps advertisers tailor their strategies.  3rd party cookies are only accessible on a domain if that domain allows outside parties’ cookies. 

How Are 3rd Party Cookies Different from 1st Party Cookies?

The main difference is the domain the cookie lives on. A first-party cookie is created by the website you’re currently browsing, while a 3rd party cookie is created by a different site altogether. 

For a 3rd party cookie to load, the website you’re browsing needs to load that 3rd party server’s code. For a 1st party cookie, any code on the domain could potentially read and set the cookie. A 3rd party cookie needs code from the publishing domain in order to read and set the cookie.

Why Are 3rd Party Cookies Important for My Business?

One of the most common uses for 3rd party cookies is targeted advertising. Because these cookies follow you from website to website as you browse, they report back your browsing history and searches. 

Have you ever searched for beach vacations and a few days later started to notice ads about beach trips on your browser? This could have been from a 3rd party cookie tracking your activity. 3rd party cookies can also be used by support chat systems provided by another service. These chat systems are operated by outside companies that need to be loaded on your domain. 

Why Is Google Chrome Removing 3rd Party Cookies?

Chrome is stepping up and offering users more privacy when browsing by removing 3rd cookies. Other browsers, such as Safari and Firefox, have already taken action and removed 3rd party cookies. Most users don’t fully understand how cookie tracking works and what information is collected by 3rd parties. Advertisers could use 3rd party cookies to track your entire browser history which critics would say is surveillance and an invasion of privacy. 

While some would argue that 3rd party cookies offer tailored ads that are helpful, most people feel the cons of invasive web tracking outweigh the pros. Google has been slower to transition, the thought being they’re trying to balance between online advertisers and personal privacy. 

Their solution is called the privacy sandbox.

What Is the Privacy Sandbox?

The privacy sandbox is a series of proposals by Google that will allow users more privacy and will still preserve the ability for advertisers to tailor ads. This initiative will replace 3rd party cookies and keep users’ data private. 

The privacy sandbox will lump users with similar browsing histories together, allowing advertisers to target groups with tailored ads without seeing an individual’s personal data. Google created the privacy sandbox to avoid blocking the user’s browser history altogether, keeping advertisers away from less transparent forms of tracking data. 

Users will still have the ability to change settings and opt-out, but by default, the privacy sandbox will offer more shielding from companies looking to collect personal browser habits.

What Will Replace 3rd Party Cookies?

Despite some of the privacy concerns, 3rd party cookies have value and provide valuable information. So, with Chrome removing 3rd party cookies, what will replace them? Some of the notable options are:

  •  Identity Graphs
  • Conversion Measurement APIs
  • Contextual Advertising
  •  Aggregate Reporting APIs
  • Trust Tokens
  • Capped Privacy Budgets
  • Federated Learning of Cohorts (FLoc)

Identity Graphs

An identity graph is a database or table of user-profiles and identifiers that are tied to users. The profiles are generic types of users that could be assigned to a group based on certain qualities. 

Some examples would be a new homeowner profile or a recently retired profile. Identity graphs can also contain personal information such as an address, birthday, mobile phone, and email. All this information can be combined to create an advertising plan specific for a user based on profile and personal information.

Conversion Measurement APIs

A more anonymous way to track the success of an advertising campaign is the conversion measurement API. When a user clicks on an advertisement, an API call is made signaling that the ad was interacted with. The API call can attach information like campaign id, or click id, or the time and date of the interaction. 

When the user gets to the advertiser’s website, the API information can be tracked to see if that visitor makes a purchase. Conversion measurement APIs can track how effective ads are on visitors without using potentially invasive 3rd party cookies

Contextual Advertising

Contextual advertising is an approach based on webpage content instead of user behavior. This is a way of targeting based on website content or mobile applications, not the users who browse them. 

Contextual advertising reads the text of a page and searches for keywords or phrases and loads advertisements based on those search results. Users are kept anonymous since the targets are solely based on the webpage content. 

Aggregate Reporting APIs

When looking to get the big picture of advertising campaigns, aggregate reporting APIs are a great option. These reports would be used for seeing the performance of advertisements across multiple metrics, which will help to give a better sense of overall performance. 

Examples could be reports of which ads perform the best by age group, or what types of ads have the highest level of interaction. Aggregate reporting APIs can vary widely, but when combined, they help give you a good idea of the overall effectiveness of advertisements. 

Trust Tokens

An anonymous way to verify users is by using trust tokens. Trust tokens work by assigning users an encrypted token that is stored in the user’s browser. This trust token can then be used to authenticate a user without requiring any private information. 

The token will stay valid during the session and allow the user to browse the domain securely. The user’s activity can then be tracked and stored for research without requiring any additional personal information. 

Capped Privacy Budgets

Capped privacy budgets are a way of limiting the number of private information advertisers can see. Giving advertisers access to some personal information can be helpful for making ads more targeted and relevant. If advertisers exceed the cap amount they could be restricted from advertising on the site.  By limiting the amount of personal information that is collected, users can browse with more privacy and less intrusion.

Federated Learning of Cohorts (FLoc)

The federated learning of cohorts (FLoc) is a new approach to track ad performance that uses machine learning to group users. The FLoc approach can gather browser history, the content of webpages or other specific factors to assign a user to a cohort. The code that creates the user cohort would live on the browser, keeping the users’ private information from being uploaded elsewhere. The browser can then expose the cohort so that advertisers can use this to target ads specific to the user. Federated learning of cohorts is an excellent alternative to 3rd party cookies because it gives advertisers the data they are looking to track while keeping users private information safe. 

How Will This Affect My Business?

If your business relies on 3rd party cookies, you’ll need to plan for an alternative moving forward. With support from Chrome ending, businesses will need to adapt to the new system Chrome implements. If your website allows advertisers that use 3rd party cookies, you’ll need to plan with them. Kissmetrics can help your business prepare for Chrome’s replacement to 3rd party cookies. 

How Can My Business Prepare for the Removal of 3rd Party Cookies?

If your business is using 3rd party cookies you’ll need to pivot to a new way of tracking advertisement performance. Kissmetrics has the tools to track user behavior and provide you with the data needed to keep tabs on your performance. With Kissmetrics you’ll be able to analyze your users’ behavior in any browser while keeping their personal data secure. 


Chrome removing its support of 3rd party cookies is a move intended to give users a more secure browsing experience. This can present a challenge to digital marketers who rely on these cookies to target ads to specific users. Ultimately, digital marketers will need to shift to Chrome’s replacement system when it is officially rolled out or implement a behavioral analytics tool like Kissmetrics. 



Google Effort to Kill Third-Party Cookies in Chrome Rolls Out in April |

ID graphs: The Path to Identity Resolution |

Federated Learning of Cohorts | Github