How do I determine what version of Apache I'm using?

Copy and paste this link into your browser.

file:///Library/Documentation/Services/apache/index.html.html

If you can find this page then the version will be indicated. If you can't find this page, then do a search for Apache.

If you're using the stock Apache, it's 1.3 on regular OS X. I think it's Apache 2 on OS X Server, but I'm not certain.

If you're asking because you've installed Apache 2, but want to make sure it's the one that's running and not the stock Apache, one way to tell is to examine the headers it returns. This Terminal command will show your headers (just enter it and hit the "return" key):

<pre class="command">curl -I http://localhost</pre>
Here's what I get:

<pre class="command">HTTP/1.1 200 OK
Date: Mon, 02 Jul 2007 13:09:06 GMT
Server: Apache/1.3.33 (Darwin) PHP/5.2.0 mod_perl/1.29
Content-Type: text/html</pre>
As you can see, I have the stock Apache, but I've installed PHP5.

charlie

To add to Charles' post, if apache isn't running or not set up properly (I get a "can't connect" message for his curl command), you can get the version with:

ibook:~ michaelc$ httpd -v
Server version: Apache/1.3.33 (Darwin)
Server built: Mar 20 2005 15:08:27