Do Not Track

Universal Web Tracking Opt Out



Do Not Track is a technology and policy proposal that enables users to opt out of tracking by websites they do not visit, including analytics services, advertising networks, and social platforms. At present few of these third parties offer a reliable tracking opt out, and tools for blocking them are neither user-friendly nor comprehensive. Much like the popular Do Not Call registry, Do Not Track provides users with a single, simple, persistent choice to opt out of third-party web tracking.

Do Not Track signals a user’s opt-out preference with an HTTP header, a simple technology that is completely compatible with the existing web. While some third parties have committed to honor Do Not Track, many more have not. In February 2012, the major online advertising trade groups pledged at the White House to support Do Not Track by year-end; that promise remains unfulfilled. Efforts to standardize Do Not Track in the World Wide Web Consortium have resulted in deadlock, despite frequent urging by American and European policymakers.

We believe that Do Not Track could be a success, but at this stage, must be implemented through either a legal or technical requirement. In the interim, novel technical countermeasures—like the Cookie Clearinghouse—hold promise for providing simple and effective user choice over web tracking.

Did you know...

Behavioral advertising accounts for less than 5% of U.S. online advertising revenue. There are simple technologies for delivering advertising, analytics, and social features without tracking. Advertising industry self-regulation does not allow you to opt out of tracking, just seeing tracking-based ads. There is no industry self-regulation of analytics and social tracking. Studies have consistently shown that Americans overwhelmingly oppose web tracking.

For users

How to enable: FF, IE, Safari, Chrome, Opera
Websites that honor Do Not Track

Developer resources

Cookbook: how to build third-party advertising, analytics, and social features without tracking
FourthParty Web Measurement Platform
Reference Browser Extensions
Web Application Templates
Web Server Configurations

Policy materials

FTC Comment: comprehensive policy statement
Annotated Bibliography: related research

The DoNotTrack.Us website is maintained by Stanford and Princeton researchers Jonathan Mayer and Arvind Narayanan. We are affiliated with the Center for Internet and Society at Stanford Law School.

The broader Do Not Track effort is a collaboration of numerous researchers, advocacy groups, and technology companies. We have worked closely with Alex Fowler, Sid Stamm, and other Mozillans; Peter Eckersley, Lee Tien, Rainey Reitman, and other EFFers; Alissa Cooper; Chris Soghoian; Ashkan Soltani; Harlan Yu; and many more.

Creative Commons LicenseAll text on is licensed under a Creative Commons Attribution 3.0 Unported License.