Navigator: doNotTrack property
Deprecated
Avoid using this feature in new projects. This feature may be a candidate for removal from web standards or browsers.
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.
The Navigator.doNotTrack property returns the user's Do Not Track setting, which indicates whether the user is requesting websites and advertisers to not track them.
The value of the property reflects that of the DNT HTTP header, i.e., values of "1", "0", or null.
The whole DNT (Do Not Track) specification has been discontinued. The mechanism design was flawed, because it was a cooperative feature between users, websites, and browsers. The idea is that the user tells the website to not track them, and the website would comply. However, there is no strict enforcement of this policy, so advertisement websites ignored the DNT header and tracked users anyway. The feature is therefore useless. Moreover, it is harmful as it leaves more user fingerprint in the header, which can be used to track users even more.
Browsers are exploring other more enforceable privacy features, such as global privacy control, restriction to third-party cookies, and more.
Value
A string or null.
Examples
console.log(navigator.doNotTrack);
// prints "1" if DNT is enabled; "0" if the user opted-in for tracking; otherwise null
Specifications
Part of the discontinued Tracking Preference Expression (DNT) specification.
Browser compatibility
See also
DNTHTTP header