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.
In the May 2001 survey we received responses from 29,031,745sites.
Market Share for Top Servers Across All Domains August 1995 – May 2001
Top Developers
| Developer | April 2001 | Percent | May 2001 | Percent | Change |
|---|---|---|---|---|---|
| Apache | 17932251 | 62.55 | 18069603 | 62.24 | -0.31 |
| Microsoft | 5918319 | 20.64 | 5958734 | 20.52 | -0.12 |
| iPlanet | 1798490 | 6.27 | 1813244 | 6.25 | -0.02 |
Top Servers
| Server | April 2001 | Percent | May 2001 | Percent | Change |
|---|---|---|---|---|---|
| Apache | 17932251 | 62.55 | 18069603 | 62.24 | -0.31 |
| Microsoft-IIS | 5916724 | 20.64 | 5957240 | 20.52 | -0.12 |
| Netscape-Enterprise | 1762872 | 6.15 | 1778958 | 6.13 | -0.02 |
| Zeus | 779209 | 2.72 | 798745 | 2.75 | 0.03 |
| Rapidsite | 402829 | 1.41 | 407488 | 1.40 | -0.01 |
| AOLserver | 272815 | 0.95 | 377264 | 1.30 | 0.35 |
| thttpd | 369930 | 1.29 | 370282 | 1.28 | -0.01 |
| tigershark | 200620 | 0.70 | 215321 | 0.74 | 0.04 |
| WebSitePro | 119586 | 0.42 | 118762 | 0.41 | -0.01 |
| ConcentricHost-Ashurbanipal | 106443 | 0.37 | 109879 | 0.38 | 0.01 |
Active Sites
| Developer | April 2001 | Percent | May 2001 | Percent | Change |
|---|---|---|---|---|---|
| Apache | 7015250 | 61.67 | 7230089 | 61.53 | -0.14 |
| Microsoft | 2961984 | 26.04 | 3062949 | 26.07 | 0.03 |
| iPlanet | 294594 | 2.59 | 324722 | 2.76 | 0.17 |
Albeit released closer to June 1 than May 1, the Netcraft survey of Web servers has the Apache Web server slightly declining in market share.
iPlanet is the sum of sites running iPlanet-Enterprise, Netscape-Enterprise, Netscape-FastTrack, Netscape-Commerce, Netscape-Communications, Netsite-Commerce & Netsite-Communications.
Microsoft is the sum of sites running Microsoft-Internet-Information-Server, Microsoft-IIS, Microsoft-IIS-W, Microsoft-PWS-95, & Microsoft-PWS.