FLoC (pronounced "flock") stands for Federated Learning of Cohorts and is the latest ad targeting technology that Google is experimenting with. Since the announcement of the eradication of third party cookies on the Chrome browser, publishers and advertisers have been in a state of uncertanity for almost two years. The promised day of eradication is nearing and nobody still has any clue on what to do in the post-cookie-less world. But FLoC might be the answer to all of our woes.

What is FLoC and how does it work?

The Federated Learning of Cohorts (FLoC) is a privacy-focused solution intent on delivering relevant ads by forming groups of users based on similar interests. The technology uses an algorithm which is built into the Chrome web browser and obsersves what websites a user visits. Using the user's browsing information, the algorithm places the user into a cohort, a group consisting of thousands of other users with similar browsing habits. That cohort can then be used by publishers and advertisers to serve up targeted ads.

According to Google, the FLoC proposal shares only the cohort group to advertisers, and does not share any information on how the browser arrives at the cohort such as the users' browsing history. These cohorts can be updated over time. "We’re pleased to share the results of our FLoC experiments, which show they’re an effective privacy-focused replacement signal for third party cookies," said Chetna Bindra, Group Product Manager, User Trust and Privacy at Google in an exclusive quote for Communicate.

Is it effective?

Yes, according to Google. The company claims that based on its stimulations, cohorts are delivering 95% of the conversions per dollar spent when compared to cookie-based advertising. However, the effectiveness varies by the strength of the clustering algorithm and the strength of the targeted interest.

Still in the works

According to Bindra, FLoC is at the at the leading edge of the current proposals. While the technology is still in its testing phase, Google will make FLoC-based cohorts available for the global public in March. By Q2, advertisers can start testing FLoC-based cohorts in Google Ads. "We’ll make our FLoC-based cohorts available for public testing in March and we encourage robust experimentation and feedback," said Bindra.