get the parent url of iframe in PHP

Question

I am creating a widget that would load in a IFrame and users will be able to place the widget on their own website. How would I get the URL of the website that is using the

Answer 1

Assuming your widget's URL doesn't do any redirects, etc., you should be able to use:

document.referrer

from within the javascript inside your iframe and it should contain the URL of the parent page. This seems to be what YouTube does for tracking in their iframe embed codes.