Limited support Use with care and provide a fallback when broad support matters.

Topics

The browsingTopics() method of the Document interface returns a promise that fulfills with an array of objects representing the top topics for the user, one from each of the last three epochs. These topics could then be returned to the ad tech platform in a subsequent fetch request. By default, the method also causes the browser to record the current page visit as observed by the caller, so the page's hostname can later be used in topics calculation.

Embedded

Browser support

Feature Desktop Mobile
Chrome
Edge
Firefox
Safari
Chrome Android
Safari iOS
browsingTopics
Deprecated Non-standard
126
126
126
HTML attribute
allow (browsing-topics)
Deprecated Non-standard
115
115
115
browsingtopics
Deprecated Non-standard
126
126
126
DOM API
init_browsingTopics_parameter
Deprecated Non-standard

`init.browsingTopics` parameter
126
126
126
browsingTopics
Deprecated Non-standard

The browsingTopics property of the HTMLIFrameElement interface is a boolean specifying that the selected topics for the current user should be sent with the request for the associated iframe's source in a Sec-Browsing-Topics header. This reflects the browsingtopics HTML attribute.
126
126
126
Request (init browsingTopics parameter)
Deprecated Non-standard

`init.browsingTopics` parameter
126
126
126
Other
Observe-Browsing-Topics
Deprecated Non-standard

The HTTP Observe-Browsing-Topics response header is used to mark topics of interest inferred from a calling site's URL (i.e., the site where the ad tech iframe is embedded) as observed in the response to a request generated by a feature that enables the Topics API. The browser will subsequently use those topics to calculate top topics for the current user…
115
115
115
browsing-topics
Deprecated Non-standard

The HTTP Permissions-Policy header browsing-topics directive controls access to the Topics API.
115
115
115
Sec-Browsing-Topics
Deprecated Non-standard

The HTTP Sec-Browsing-Topics request header sends the selected topics for the current user along with the associated request, which are used by an ad tech platform to choose a personalized ad to display.
115
115
115
1+Supported (version) Not supported ※Has note Sub-feature descriptions sourced from MDN Web Docs (CC BY-SA 2.5)

Syntax

JAVASCRIPT 
const topics = await document.browsingTopics();
for (const topic of topics) {
  console.log('Topic:', topic.topic, 'Version:', topic.version);
}

Use cases

  • Use Topics

    Use Topics when standard HTML needs a more specific platform feature, semantic signal, or browser capability.

  • Handle edge cases

    Apply Topics to solve a focused requirement without redesigning the whole page architecture.

Cautions

  • Test Topics in your target browsers and input environments before depending on it as a primary behavior.
  • Provide a fallback path or acceptable degradation strategy when support is still limited.

Accessibility

  • Make sure Topics supports the intended task without making the page harder to perceive, understand, or operate.

Related links