Privacy

Topics API — Definition & Explanation

A Google Chrome Privacy Sandbox proposal that replaces third-party cookie-based tracking with a system where the browser determines user interest topics based on browsing history and shares a limited set of topics with advertisers.

How Topics API Works

The Topics API classifies browsing history into a taxonomy of 350+ topics, stores the top 5 topics from the past 3 weeks locally, and exposes a random selection to requesting ad tech parties during ad auctions.

Why Topics API Matters for Publishers

Topics API adoption could help publishers maintain some level of interest-based targeting signal after cookie deprecation, reducing the CPM impact for publishers who rely on behavioral targeting.

Frequently Asked Questions

Does Topics API fully replace third-party cookies for targeting?

No. Topics provides coarse-grained interest signals, not the granular user-level data cookies provided. It's one of several signals that will replace cookies.

Is Topics API live in Chrome?

Topics API is available in Chrome for testing. Broad adoption by the industry is still developing as the ecosystem evaluates its effectiveness.

What taxonomy does Topics API use?

Topics API uses a taxonomy of approximately 350 topics organized in a hierarchy, covering categories from News to Finance to Sports.

Related Terms

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