Anonymous on the web? Think again...

[NickFitz]

Unique, 17.22 in Chrome, IE8 & FF3. I was expecting different results from different browsers, if it uses plugins to measure this stuff?

Plugins generally install for all browsers that support the Netscape Plugin API, which is just about everything. Plugins should not be confused with such things as Firefox extensions, IE Browser Helper Objects, Opera widgets, and other such browser-specific thingies :

For example, Flash is a plugin, so the same copy should be used by all browsers. Note the careful use of the word "should" there.

[d000hg]

Plugins generally install for all browsers that support the Netscape Plugin API, which is just about everything. Plugins should not be confused with such things as Firefox extensions, IE Browser Helper Objects, Opera widgets, and other such browser-specific thingies :

For example, Flash is a plugin, so the same copy should be used by all browsers. Note the careful use of the word "should" there.

Still confused then that I get the same score for IE. I doubt I have the same Flash version, let alone things like Silverlight, across my browsers. I also have at least a couple of custom plugins like QuakeLive and some random 3D rendering plugin.

Why "should" all browsers support Netscape's API? IE has technically been around longer than any current mainstream browser after all

[NickFitz]

Still confused then that I get the same score for IE. I doubt I have the same Flash version, let alone things like Silverlight, across my browsers. I also have at least a couple of custom plugins like QuakeLive and some random 3D rendering plugin.

Why "should" all browsers support Netscape's API? IE has technically been around longer than any current mainstream browser after all

That's the plugin API; it's named after Netscape, where it originated, but it's still the de facto standard implemented by all browsers. Otherwise, they'd each need their own copy of the plugin, which would defeat the whole purpose of browser manufacturers adopting that API, which they did because once upon a time everything had to work the way Netscape did. Microsoft would have looked pretty silly releasing a browser that couldn't use the Flash version 1 plugin, which was written to work with NN.

It's like cookies. There's an RFC defining how they should work, but everybody ignores it: modern browsers still use the original Netscape Cookie Spec (with a few bug fixes), which differs in several obscure points from the RFC but happens to be what was always supported.

Remember, lots of IE's behaviour was deliberately reverse engineered from Netscape Navigator's behaviour, because NN was the de facto standard in the mid-to-late-Nineties. In fact, a number of parts of the new HTML5 spec relating to parsing are simply codifying behaviour that originated in Netscape Navigator 1, 2 or 3, which was then reverse engineered by Microsoft for IE3+, and was then re-reverse engineered by newer browsers wanting to be compatible with the way IE had tried to be compatible with NN

The custom plugins are probably BHOs (in IE) or extensions (in Firefox). These aren't the same as plugins (which conform to the Netscape Plugin API), except from a user's point of view

EDIT: Netscape Plugin API.

EDIT AGAIN: Ah yes, I believe MS moved away from the NPAPI in more recent versions of IE (they hate doing things correctly), but they still support the NPAPI way of exposing the presence of plugins in the browser for backwards compatibility, which is why the test shows the same results. Well, that's my theory

[RichardCranium]

Your browser fingerprint appears to be unique among the 197,318 tested so far.

Currently, we estimate that your browser has a fingerprint that conveys at least 17.59 bits of identifying information.

The list of fonts did it. Windows ME upgraded to XP with Office 97 fonts + a selection of wargaming fonts and sci-fi fonts.