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http header

Tk header

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[!NOTE] The DNT (Do Not Track) specification has been discontinued. See doNotTrack for more information. An alternative is Global Privacy Control, which is communicated to servers using the Sec-GPC header, and accessible to clients from globalPrivacyControl.

The HTTP Tk response header indicates the tracking status that applied to the corresponding request.

Header type [Response header](https://developer.mozilla.org/en-US/docs/Glossary/Response%20header)

Syntax

Tk: !  (under construction)
Tk: ?  (dynamic)
Tk: G  (gateway or multiple parties)
Tk: N  (not tracking)
Tk: T  (tracking)
Tk: C  (tracking with consent)
Tk: P  (potential consent)
Tk: D  (disregarding DNT)
Tk: U  (updated)

Directives

  • !
    • : Under construction. The origin server is currently testing its communication of tracking status.
  • ?
    • : Dynamic. The origin server needs more information to determine tracking status.
  • G
    • : Gateway or multiple parties. The server is acting as a gateway to an exchange involving multiple parties.
  • N
    • : Not tracking.
  • T
    • : Tracking.
  • C
    • : Tracking with consent. The origin server believes it has received prior consent for tracking this user, user agent, or device.
  • P
    • : Potential consent. The origin server does not know, in real-time, whether it has received prior consent for tracking this user, user agent, or device, but promises not to use or share any DNT:1 data until such consent has been determined, and further promises to delete or permanently de-identify within 48 hours any DNT:1 data received for which such consent has not been received.
  • D
    • : Disregarding DNT. The origin server is unable or unwilling to respect a tracking preference received from the requesting user agent.
  • U
    • : Updated. The request resulted in a potential change to the tracking status applicable to this user, user agent, or device.

Examples

A Tk header for a resource that claims not to be tracking would look like:

Tk: N

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

This response header doesn’t trigger any browser behavior, so browser compatibility is irrelevant.

See also