Regex: How to match IP address in RFC1918 private IPV4 address ranges (in Python)?

Question

RFC1918 defines private IPv4 addresses as those that fall within any of the following ranges:

10.0.0.0 - 10.255.255.255
172.16.0.0 - 172.31.255.255
192.168.0.0 -         


        

Answer 1

The following regexp should work:

^(?:10|127|172\.(?:1[6-9]|2[0-9]|3[01])|192\.168)\..*

DEMO