FLoC / Topics API

What Is the Topics API?

The Topics API is part of Google’s Privacy Sandbox initiative and signals where digital advertising is heading: away from individual user surveillance, toward privacy-friendly targeting based on interest groups. For advertisers, this means preparing now for first-party data strategies and contextual targeting, rather than banking on the continued existence of cookie-based methods.

FLoC (Federated Learning of Cohorts) was Google’s experimental approach to interest-based advertising as a third-party cookie alternative in Chrome. The idea was to group users into cohorts based on their browsing behavior — users with similar interests would receive similar ads without their individual data being shared with third parties. After significant privacy criticism, Google discontinued FLoC and is now working on the Topics API as a successor — a more moderate approach with fewer privacy concerns.

Technically, FLoC was designed to run in the browser on the user’s device without transmitting data to Google servers. The browser would locally analyze browsing history, determine cohort IDs, and pass those cohort IDs (not the actual data) to advertising platforms. The Topics API works similarly but shows users more transparently which topics their browser has assigned, and allows them to block or delete those topics. This is more privacy-friendly but functionally similar — Google is trying to enable interest-based advertising without third-party tracking.

For marketers and website owners, this means: prepare for a future without third-party cookies. Build first-party data collection (newsletters, CRM, user accounts). Use the Google Topics API when available for audience segmentation. Start testing privacy-friendly tracking methods now. In the SEO context this is less critical, but for Google Ads marketers it matters: without cookies, targeting becomes harder, making Conversion tracking via Enhanced Conversions and First-Party Data even more important. Ensure your website has cookie consent banners and is GDPR-compliant. The future of targeting lies in first-party data, not third-party cookies.