Tk header

Deprecated

Avoid using this feature in new projects. This feature may be a candidate for removal from web standards or browsers.

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Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.

Note: The DNT (Do Not Track) specification has been discontinued. See Navigator.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 navigator.globalPrivacyControl.

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

Header type	Response header

Syntax

http

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.