Tk header

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see thecompatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

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. SeeNavigator.doNotTrack for more information.An alternative isGlobal Privacy Control, which is communicated to servers using theSec-GPC header, and accessible to clients fromnavigator.globalPrivacyControl.

The HTTPTkresponse 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 oftracking 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 exchangeinvolving multiple parties.
N: Not tracking.
T: Tracking.
C: Tracking with consent. The origin server believes it has received prior consent fortracking this user, user agent, or device.
P: Potential consent. The origin server does not know, in real-time, whether it hasreceived prior consent for tracking this user, user agent, or device, but promises notto use or share anyDNT:1 data until such consent has been determined,and further promises to delete or permanently de-identify within 48 hours anyDNT:1 data received for which such consent has not been received.
D: Disregarding DNT. The origin server is unable or unwilling to respect a trackingpreference received from the requesting user agent.
U: Updated. The request resulted in a potential change to the tracking statusapplicable to this user, user agent, or device.