[RickJ]

w3schools.com says Firefox users are now at about 33% of all internet users. I find this hard to believe. In a national news article I read recently about the new Safari, they said Firefox users were at about 20%.

Who is the most reputable source for a good guestimate on what percentage Firefox users really are?

Thanks!

[Superfly999]

Hmm, I don't know about a good source on the guestimate. But I would believe that 33% or actually more are using Firefox. I know that I use it and everyone else I know does :P.

[Curlyben]

I certainly would go with W3's stats, as they are nonaffiliated to any company.
The 20% for FF users in the Safari piece is old information, FF passed that landmark ages ago.

[Northwind_Dagas]

I would NOT go with W3's stats:

W3Schools is a website for people with an interest for web technologies. These people are more interested in using alternative browsers than the average user. The average user tends to use Internet Explorer, since it comes preinstalled with Windows. Most do not seek out other browsers.

These facts indicate that the browser figures above are not 100% realistic. Other web sites have statistics showing that Internet Explorer is used by at least 80% of the users.

WebReference.com puts Firefox at about 20%. (July 1, 2007)
TheCounter.com puts Firefox at about 12%. (June 2007)

The simple truth is that no one source will be completely accurate. It is going to largely depend on the demographics of the people that visit a given website as to what numbers they see. To be 100% accurate, you would need to look at the stats from a website that 100% of internet users visit, and I don't think that website exists.

If you are trying to find out so you can make design decisions, try looking at stats from other sites that share your same target audience.