Simon Willison’s Weblog

How can I determine which web server a particular website is using (Apache, IIS, Nginx, etc)?

5th January 2011

My answer to How can I determine which web server a particular website is using (Apache, IIS, Nginx, etc)? on Quora

If you’re on Linux or OS X, use curl with the -I option (to make a HEAD request and see the HTTP headers):

$ curl -I www.op3intl.com
HTTP/1.1 200 OK
Date: Thu, 06 Jan 2011 03:31:28 GMT
Server: Microsoft-IIS/6.0

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