IP address regex python

Question

I am having an issue with Regular expression, I need the most efficient regex that match IP address and in range of 255 only.

I tried this one "ip_pattern = '\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}'" , but it does match even numbers over 255, such as 321.222.11.4

Answer 1

This should do it:

^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$

Answer 2

Use this Regex. It will match and check the IP range within 255.

\b(?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]?[0-9]).(?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]?[0-9]).(?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]?[0-9]).(?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]?[0-9])\b