Netcraft posts June 2001 Web survey

More Web numbers than you can shake a stick at

The Netcraft Web Server Survey is a survey of Web Server software usage on Internet connected computers. We collect and collate as many hostnames providing an http service as we can find, and systematically poll each one with an HTTP request for the server name.

Top Servers

Server May 2001 (%) June 2001 (%) Change
Apache 18069603 62.24 18466153 63.02 0.78
Microsoft-IIS 5957240 20.52 5972321 20.38 -0.14
Netscape-Enterprise 1778958 6.13 1768673 6.04 -0.09
Zeus 798745 2.75 810108 2.76 0.01


Active Sites

Developer May 2001 % June 2001 % Change
Apache 7230089 61.53 7346025 62.42 0.89
Microsoft 3062949 26.07 3076623 26.14 0.07
iPlanet 324722 2.76 273293 2.32 -0.44


Counting Computers Running the Web

One of the common observations made about the Web Server Survey is that it counts hostnames rather than physical computers, and so is not a suitable metric to indicate hardware installed base or licence sales.

Technically sophisticated hosting companies can run thousands of sites on a single computer, and the great majority of the world's Web sites are located at hosting and co-location companies rather than on peripheral networks.

Building on the operating system detection techniques used by the What's that site running? query and Netcraft's commercial research, we have attempted to address this.

Netcraft has developed a technique that, with an error margin, can give an indication of the numbers of actual computers we find on the Web, together with the operating system and web server software used.

By arranging for a number of IP addresses to send packets to us near simultaneously, low level TCP/IP characteristics can be used to work out, within an error margin, if those packets originate from the same computer, by checking for similarities in a number of TCP/IP protocol header fields. To build up sufficient certainty that IP addresses on the same computer have been identified many visits to the sites in the Web Server Survey are necessary, which takes place over a period of over a month.

Round robin DNS, reverse web proxies, some load balancing/failover products like Cisco LocalDirector and BIG-IP and some connection level firewalls hide a number of web servers behind a hostname.

A limitation of the technique is that only a single 'front' Web server will be counted. Additionally with some of these products the operating system detected is that of the 'front' device rather than the web server behind.

Operating Systems used by Computers running public Web Sites, March 2001

OS group % Composition
Windows 49.2 Windows 2000, NT4, NT3, Win95, Win98
Linux 28.5 Linux
Solaris 7.6 Solaris 2, Solaris 7, Solaris 8
BSD 6.3 BSDI BSD/OS, FreeBSD, NetBSD, OpenBSD
Other Unix 2.4 AIX, Compaq Tru64, HP-UX, IRIX, etc.
Other non-Unix 2.5 Mac OS, NetWare, proprietary IBM OSes
Unknown 3.6%  


Microsoft Windows has a significantly higher share of the Web when one counts by computer, rather than by host, as in the conventional Web Server Survey. The survey shows 49 per cent of the computers running the web are Windows based; a little more than all of the Unix-like operating systems combined. As some of the 3.6 per cent of computers not identified by Netcraft operating system detector will in reality be Windows systems, it would be fair to say about half of public Web Servers worldwide are run on Microsoft operating systems.

Although Apache running on various Unix systems runs more sites than Windows, Apache is heavily deployed at hosting companies and ISPs who strive to run as many sites as possible on a single computer to save costs. Windows is most popular with end-user and self hosted sites, where the host to computer ratio is much smaller.

Linux is the second most commonly used operating system. Linux has been consistently gaining share since this survey started, but, interestingly, not significantly to Windows detriment. Operating systems which have lost share have been Solaris and other proprietary operating systems, and to a small degree BSD.

One could characterise this process as Solaris being continually chased further and further up market by Intel based operating systems, with Sun in turn progressively eliminating the other proprietary Unix operating systems. Intel enjoys both the benefits of the boom in freely available Unix software and the ascent of Windows, with competing processors correspondingly marginalised in the web server market.

Sun would reasonably point out that this analysis simply counts the number of computers rather than their cost, and that a $1000 Intel machine would count the same as a $1 million system, and that while Windows matains its share in Fortune 500 companies, the relative position between Linux and Solaris is approximately reversed in these companies.

The analysis also gives some quantification of the rate at which sites migrate to Windows 2000 from NT. In March 2001, a little over a year after the introduction of the operating system 25 per cent of the computers running Microsoft operating systems are running Windows 2000.

Regional Variations

The results summarised above are from a world-wide perspective and significant variations can occur in regional analyses.

Countries with the largest proportions of Windows web servers are China, South Africa and Singapore. Countries in which Unix-like operating systems maintain the strongest lead are Poland, Hungary, Japan, Russia and Germany, with Linux strong in Poland and Hungary, and BSD in Russia and Japan, while in Finland, home country of Linus Torvalds, Windows has a tiny lead over Linux! ®

Sponsored: 10 ways wire data helps conquer IT complexity