What is Google replacing cookies with?

Google is replacing third-party cookies with a new tool called Topics API, a part of its Privacy Sandbox initiative. It is the proposed privacy-focused alternative to tracking cookies that is designed to preserve user privacy while still allowing advertisers to display relevant ads.

Topics API works by categorizing a user’s interests based on their web usage, without sharing the specific sites visited with advertisers, which has been the case with third-party cookies. The API labels each website and classifies them within a set of high-level interest groups, such as fashion, food, or travel. Users are assigned a topic based on their browsing history for a specific period of time and this grouping can then be used for targeting. Users will have the control to view the topics, remove unwanted ones, or disable them from Chrome.

Google initially introduced Federated Learning of Cohorts (FLoC) as a substitute for cookies but later abandoned it in 2022, introducing Topics API instead. The Privacy Sandbox toolkit also includes additional APIs like Attribution Reporting API and Protected Audience API.