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Do Not Track (DNT) header

Do Not Track (or DNT for short) is a browser setting that requests that a website does not track the user. When Do Not Track is turned on your browser sends an extra request header to stop tracking your activity. Do Not Track is a way to keep users online behavior from being tracked across the Internet by advertisers, analytics companies and social media websites. UltraBlock makes sure your browser always sends the Do Not Track header to improve your privacy.

First-party and Third-party services

When you visit a website your browser loads first-party content and third-party content. First-party content is created and hosted by the website your visiting itself. You can recognize it easily because it’s loaded from the same origin as the website your visiting itself. Third-party content however is content that is provided by other services like social media buttons, ads and analytics that is loaded in the background. The source of third-party content is always from a different domain.

Do Not Track is designed not to interfere with your browsing experience. There are only a few tracking restrictions for first-party websites. They may remember things about you but not share this with third-party services. When Do Not Track is enabled, third-party servies are asked to treat you as someone they don’t know and remember nothing about you. Third-party services that implement Do Not Track have to stop record information that can be traced to you when your browser sends the Do Not Track request header.

Do Not Track request header

When you visit a website your browser automatically downloads font, image and JavaScript files. For each file your browser downloads it first sends out a request header. A request header is information that your browser sends to a web server containing the details of what your browser wants and will accept back from that web server. The request header also contains the type, version and capabilities of your browser so that the web server returns compatible data. When DNT is used your browser also sends the DNT header with each request.

Companies that implement Do Not Track

Although introduced in 2012 the Do Not Track header is not implemented in many commercial services yet. A few big companies like Pinterest and Twitter are taking steps to implement Do Not Track. On the website you see what companies implemented the Do Not Track header.

Do Not Track is one of many privacy solutions. It does not aim to give you absolute online privacy, but improves it. UltraBlock always sends the Do Not Track header to improve your privacy.