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Is it at all possible to get the size of a remote file without downloading it? The file is over HTTP, not (S)FTP. I want to know this because I want to download something while connected with a limited 3G wireless plan and I don't want to use all my bandwidth in one pop. I have no access to the server, at all. So I can't do anything server-side. I am on Mac OS X. Solutions that make use of the command line are a plus, but not required.

By the way, the specific file I want information for is the MP3 download from this website.

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3 Answers 3

up vote 3 down vote accepted

You can do this by getting the Content-Length header, so long as it is HTTP.

One way of doing this on the command line is with curl, for example:

chris@chris-laptop:~$ curl -I -L
HTTP/1.1 200 OK
Date: Tue, 25 Jan 2011 22:22:51 GMT
Server: Apache/2.2.16 (Debian)
Last-Modified: Tue, 11 Jan 2011 16:32:52 GMT
ETag: "3aa003-1b0c3479-49994a2c6f500"
Accept-Ranges: bytes
Content-Length: 453784697
Content-Disposition: attachment
Content-Type: application/octet-stream

Content-Length is in bytes.

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Awesome! Thank you! – Wuffers Jan 25 '11 at 22:27
No problem! Glad you found a solution :) – Matthieu Cartier Jan 25 '11 at 22:28
1 There's also this addon that would help if you are a firefox user. – Jeshii Jan 25 '11 at 22:52

You can issue HTTP HEAD requests to get the only header data. Content-Length is what you want.

$ telnet 80
Connected to
Escape character is '^]'.

HTTP/1.1 302 Found
Content-Length: 141
Date: Tue, 25 Jan 2011 22:21:28 GMT
Connection: close
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It depends on how the server is setup and the file. With most files the server sends it in the headers, but it may be a dynamic file and therefore it doesn't know (and your browser can't guess how long it will take.

tobylane$ telnet 80


Connected to

Escape character is '^]'.


HTTP/1.1 302 Found


Date: Tue, 25 Jan 2011 22:01:22 GMT

Connection: close

I'm not sure what a good request is (GET / worked on other sites), but I hope this helps.

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What "other sites" did it work for? It would be more helpful if you would post the ones it worked for instead of one it didn't work for. – Wuffers Jan 25 '11 at 22:06
Also, just a tip. You can indent code/console output like that by four spaces to make it preformatted and a lot more readable. – Wuffers Jan 25 '11 at 22:11

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