The Scorecard

Browser Cookie controls Third-party Cookies Flash Cookies Tracking Opt-out
Firefox C some block-list control D Enabled by default F Can’t be blocked. C- Only supports “Do Not Track” header, disabled by default.
Internet Explorer ??? F Enabled by default, and sometimes sent even when disabled. F Can’t be blocked. F- Microsoft engineers originally built awesome anti-tracking technology into IE, and then their bosses made it totally useless.
Internet Explorer 9 unknown F Enabled by default, and sometimes sent even when disabled. unknown B Supports both the “Do Not Track” header and “Tracking Protection Lists”. (what is enabled by default?)
Chrome A good block-list controls
F Enabled by default, and sometimes sent even when disabled. F Can’t be blocked. D- Horrible anti-tracking support, only available as an optional extension called Keep My Opt-Outs.
Safari ??? B+ Disabled by default, but sometimes sent even when disabled. F Can’t be blocked. F No anti-tracking feature.

Explanation of topics

Cookie control

Since some sites do require cookies and you may want to allow them for sites you trust, you do not want to just block all cookies, but allow them on a site-by-site basis. The browsers are evaluated here based on how well they allow the user to block untrusted sites (should be the default) and allow trusted sites (should be an easily modifiable list).

Third-party Cookies

Cookies are required whenever you login to a website (technically, you can create a login session without cookies, but not very securely). However, most all websites also transmit cookies from third parties that are used to track your clicks and behavior across many websites. There is no legitimate use for third party cookies — their only use is to keep you under surveillance. Third party cookies should be blocked by default in all browsers.

Flash Cookies

As more people block cookies, a huge number of websites have switched to tracking people by setting special cookies via the Adobe Flash plugin. These cookies are even worse than third party cookies and are harder to get rid of. The newer browsers can be made to block flash cookies, but only in “private browsing” or “incognito” mode.

Tracking Opt-out

There are three methods of opting out of behavioral tracking:

Scorecard Notes

Firefox

Internet Explorer

Internet Explorer 9

Version 9 of Internet Explorer is much better than all the previous versions.

Chrome

Safari

How to get an “A+”

What would a browser need to do in order to score “A+” on the scorecard?