Tk Header

Table of Content

  • Syntax
  • Directives
  • Examples
  • Browser Compatibility
  • How to modify Tk header The Tk (Tracking Status) response HTTP header is primarily used to specify the tracking status that applies to a given request-response exchange. It aims at expressing the user's tracking preference to the server. This header informs the user agent (usually a web browser) about the tracking behavior of the server and whether it will comply with the user's tracking preference.


The syntax typically follows the pattern Tk: ! where ! represents the status value. For instance:

Tk: N


There are several tracking status values that can be used as directives. They include:

  1. N (Not tracking) - The server will not engage in any potential tracking.
  2. T (Tracking) - The server will perform tracking.
  3. C (Tracking with consent) - The server tracks, but claims the user has consented.
  4. P (Potentially Tracking) - The server believes it might be engaging in tracking.


Applying a Tk header that declares no tracking might look like this in an HTTP response:

HTTP/1.1 200 OK
Tk: N

Browser Compatibility

Browser Compatibility
Chrome Not Supported
Firefox Not Supported
Safari Not Supported
Opera Not Supported
Edge Not Supported

How to modify Tk header

To modify the Tk header using the ModHeader Chrome extension, follow these steps:

  1. Install the ModHeader extension in your Google Chrome browser.
  2. Click on the ModHeader icon and select 'Response headers'.
  3. Click the '+add' button and specify 'Tk' as the header name.
  4. Enter the desired tracking status value (e.g., N, T, C, P) in the 'value' field and hit 'Enter'.

Modifying the Tk header can be used to simulate different tracking settings and test how your application responds to different tracking statuses. However, please note that since browser support for the Tk header is not widespread, this technique is predominantly used for testing and development purposes.