Regex for Matching an IPv4 Address

Matches four dot-separated groups of digits in the shape of an IPv4 address.

Key points

• This simple version matches the shape but not the valid range (0-255) of each octet
• A stricter pattern constraining each group to 0-255 is significantly longer and less readable

Example

^(\d{1,3}\.){3}\d{1,3}$