The port property represents the port portion of the URL. This normally follows the hostname, but is not always available.
http://www.navioo.com:8080/index.htm, the port is equal to 8080.
<html> <head> <title> Using the port property of the Location object</title> </head> <body> <script language="JavaScript"> <!-- function show(){ alert(document.location.port); } --> </script> <form name="form1"> Click the button to get the current location.port value of the following address: <br> http://www.navioo.com <br> <input type="button" name="getport" value="Get port" onClick='show()'> <br> </form> </body> </html>