*Note: W3 Counter only lists the top 10 Browsers by Version. This is one of the reasons why Opera fluctuates between 0.7% and 1.2% in the table below, as some versions only make it into the top 10 occasionally.
*Note: W3 Counter only lists the top 10 Browsers by Version. This is one of the reasons why Opera fluctuates between 0.7% and 1.2% in the table below, as some versions only make it into the top 10 occasionally. This site counts the last 25,000 page views from each site making relativly small sites contribute a lot more to the statistics then in an overall count.
|+ '''Global usage share data from: [http://www.w3counter.com/globalstats.php W3 Counter]'''
|+ '''Global usage share data from: [http://www.w3counter.com/globalstats.php W3 Counter]'''
Revision as of 15:25, 1 September 2008
Usage share, in web browser statistics, is the percentage of visitors to a group of web sites that use a particular browser. For example, when it is said that Internet Explorer has 76% usage share, it means Internet Explorer is used by 76%[2] of visitors that visit a given set of sites. Typically, the user agent string is used to identify which browser a visitor is using.
Overestimation and underestimation
Note that measuring browser usage in terms of the number of requests (page hits) made by each user agent can be misleading. Not all requests are generated by a user, as a user agent can make requests at regular time intervals without user input. In this case, the usage of that user agent would then be overestimated. Some examples:
A web browser that refreshes the webpage at a regular time interval.
A feed reader that requests the RSS or Atom feed at a regular time interval.
Extra files like CSS hacks and JavaScript hacks are often sent to Internet Explorer.
Gecko-based browsers (such as Firefox) can link prefetch web pages, increasing hits. Link prefetching in Gecko-based browsers is used on pages with enhanced markup, including Google search results.[3]
A user who revisits a site shortly after changing or upgrading browsers may be double-counted under some methodologies; overall numbers at the time of a new version's release may be skewed.[4]
It is also possible to underestimate the usage share by using the number of requests, for example:
A graphical browser typically results in more hits than a text browser, as it downloads files referred to by the HTML document (e.g., image, CSS, and JavaScript).
Many browsers and download managers spoof a different user agent string to the web server to prevent erroneous or malicious browser sniffing which could result in receiving broken or incompatible code, or being completely blocked, and thus increasing the statistics for other browsers (as an example, prior to version 9, the Opera web browser had "Identify as Internet Explorer" as the default user setting)
Text-based and audio-based browsers do not download any webbugs at all.
Gecko-based browsers since Firefox 1.5 and Opera uses fast Document Object Model (DOM) caching. JavaScript is only executed on pageload from net or disk cache, but not if it is loaded from DOM cache. This can have an impact on JavaScript based tracking of browser statistics.[1]
Firefox blocked Alexa toolbars from its extension page for quite some time, this makes the estimates of Net Applications inaccurate.
Ad filtering is popular through methods such as the Firefox extension Adblock.
A more accurate estimate of the number individual people visiting a web site can be made by considering unique IP address and cookies in addition to page hits.[citation needed]
Note: W3 Counter only lists the top 10 Browsers by Version. This is one of the reasons why Opera fluctuates between 0.7% and 1.2% in the table below, as some versions only make it into the top 10 occasionally. This site counts the last 25,000 page views from each site making relativly small sites contribute a lot more to the statistics then in an overall count.
Chuck Upsdell's Browser Stats lists web stats from many different stats sources and gives the approximate current usage share of the most popular layout engines.
W3Schools' Browser Statistics lists the web stats only from the W3 Schools site, which gives the approximate usage share of browsers among "people with an interest for web technologies."