May 2003 Web Server Survey
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 2003 survey we received responses from 40,444,778 sites.
Market Share for Top Servers Across All Domains August 1995 - May 2003

Top Developers
| Developer | April 2003 | Percent | May 2003 | Percent | Change |
|---|---|---|---|---|---|
| Apache | 25090844 | 62.57 | 25290478 | 62.53 | -0.04 |
| Microsoft | 11007434 | 27.45 | 10989025 | 27.17 | -0.28 |
| Zeus | 789324 | 1.97 | 780936 | 1.93 | -0.04 |
| SunONE | 415999 | 1.04 | 420398 | 1.04 | 0.00 |
Active Sites
| Developer | April 2003 | Percent | May 2003 | Percent | Change |
|---|---|---|---|---|---|
| Apache | 11961421 | 66.17 | 12244043 | 66.52 | 0.35 |
| Microsoft | 4548174 | 25.16 | 4535721 | 24.64 | -0.52 |
| Zeus | 285797 | 1.58 | 286840 | 1.56 | -0.02 |
| SunONE | 220481 | 1.22 | 217857 | 1.18 | -0.04 |
Totals for Active Servers Across All Domains June 2000 - April 2003

SunONE 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.