Site and Sub-Site GUID's with STSADM

The following command displays the GUID's of all the Site Collections, root site and all it's sub-site on command prompt using stsadm utility. Same can also be achieved using PowerShell.

Displays the IDs and site map status for all site collections and subsites in the content database.
stsadm -o enumallwebs -databasename
 
Note: Replace with actual content database name. Go to Central admin > content database for the particular web application.
 
Cheers!!!