I am trying to get the subnet mask from a start and end ip in PHP.
Eg; 18.104.22.168 and 22.214.171.124 is 255.255.224.0
But there doesn't seem to be any built in function for this? Everything I have searched refers to CDIR and trying to get all the ips etc so it seems I am trying to go the other way.
Anyone have any ideas?