MSIE|!MSIE Revisited

Some time ago, I performed a “test to determine when MSIE is not MSIE”:, and I just retested with numbers from March 2003.

The short version is this:
Through the User-Agent string, 58.9% of my visitors *claim* to be using MSIE, while only 38.1% of my visitors are fetching the MSIE-specific stylesheet included with conditional comments.
35.2% of browsers that claim to be MSIE aren’t. 84.2% of browsers that use a faked MSIE UA string, are using Opera. Opera’s “real” market share among CSS-capable browsers is 45.3%.
*Update:* Disclaimer: Although, I use the phrase “market share”, it should not in any way be confused with a _general_ market share for browsers. The literal figures are valid only in the context of the sampled site. The point is the overrepresentation. This is also explained in the “previous article on the same subject”:

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  1. Dan Michael

     /  2003-05-14

    The problem is that the default settings for Opera was “Identify as MSIE” in some versions (maybe even the latest, can’t remember that actually). This probably gives the best browsing experience because many some sites display an error message when they encounter an unknown browser like Opera. However, Opera’s part of the browser statistics goes the wrong way.
    One of the sites that only works if you identify Opera as MSIE is I sent them a mail and asked them why they do this, since there are no difference between the act of Opera 7 with different identification. I got the common answer back: little time, small budget, etc.. but what was quite funny was one of the arguments why they wouldn’t use some time to fix it: 98,2% of their users used MSIE! That’s pretty natural when you must use MSIE or claim to use MSIE to get the site to work! Some webmasters are stupid 🙁

  2. Since these stats are so different from generally accepted ones it seems to me that you need to surround them with more detail. For instance, what is the sample size? Where is the sample site? What is the language of the sample site? What connection do you have with Opera? etc.

  3. This article is a follow-up on an article I “wrote earlier”: Read that article, and it will answer a few of your questions directly, and it’ll give you data to calculate some of the others, and it carries this disclaimer:
    bq. This test is made from a sample from a period of only 64 hours and 9 minutes on a relatively low-traffic site. The market share should not be confused with MSIE’s general market share, and the test is here only to give an indication on how common it is for other browsers to misrepresent themselves as Internet Explorer.
    Adding to that: I am not an employee of Opera, nor do I have any professional connection with Opera.