Can anyone recommend a (free) tool to test if a web server is using http compression?

Question

I see there are plenty of web sites out there that will do this, but I'd really like something I can run to diagnose our internal intranet servers that aren't exposed to the internet.

And, with the budget of this project, free is pretty much my only option. Does anyone have any cool tools they can recommend? Or is there some cool firefox widget I don't know about?

Thanks!

Answer 1

If you use Firebug you can go into the "net" tab and look at all the resources downloaded. Look for "Content-Encoding", that'll tell you if the server is sending the data using gzip/etc.

Answer 2

You could use LiveHeader for Firefox to take a look at the response headers.

Answer 3

I use "Live HTTP headers", a FF addon.

In the headers, you should see Content-Encoding: {...}

For stackoverflow.com, I see: "Content-Encoding: gzip"

Edit: fixed the header to look for, per the comments' suggestion.

Answer 4

Simply look at the HTTP headers your server is sending out. The content-encoding field should contain information on compression.

You can use Wireshark to monitor your network interface, including communications between your servers, which will allow you to see the raw headers and payload.

Answer 5

You can also use fiddler.

http://www.fiddlertool.com/fiddler/

Answer 6

If you don't have firefox or don't want to install some extension just to check if the site supports compression, you can use plain old telnet:

telnet stackoverflow.com 80
Trying 69.59.196.211...
Connected to stackoverflow.com.
Escape character is '^]'.
HEAD / HTTP/1.0
Host: stackoverflow.com
Accept-Encoding: gzip, deflate

HTTP/1.1 200 OK
Cache-Control: private
Content-Length: 26213
Content-Type: text/html; charset=utf-8
Content-Encoding: gzip
Expires: Mon, 09 Mar 2009 18:20:28 GMT
Vary: Accept-Encoding
Server: Microsoft-IIS/7.0
Date: Mon, 09 Mar 2009 18:20:27 GMT
Connection: close

Answer 7

I've just been informed from meatspace that the firefox developer's toolbar also has a view headers option, so you can check the encoding type there as well.

Answer 8

Yet another Firefox addon: HttpFox.