How to get page id of a facebook page

Question

I need to fetch page id of a facebook page of a given URL in graph API. e.g this is the URL http://www.facebook.com/platform and I want to get the page id of this facebook page.

Answer 1

The answers given before this one (Oct 27, 2015) no longer work.

What works right now is to go to the page or user's Facebook page, and grep the source for fb://page/\d+ or fb://profile/\d+.

Example:

https://www.facebook.com/idorecall/

contains

fb://page/1605841049661522

https://www.facebook.com/dandasco

contains

fb://profile/100002764094643

Try this on the command line:

curl -skA "Mozilla/5.0" https://www.facebook.com/idorecall/ | grep -oE "fb://[^\"]+"