IPv4 Address Regex

Validate four-octet IPv4 addresses with accurate octet range enforcement (0 to 255 per segment).

PATTERN

//g

TEST STRINGHIGHLIGHTED MATCHES (0 matches)

Valid: 192.168.1.1, 10.0.0.1, 255.255.255.0
Invalid: 256.0.0.1, 192.168.1, 1.2.3.4.5

Regex Cheatsheet

COMMON PATTERNS

SYNTAX REFERENCE

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Validate IP address whitelist entries and server firewall configuration rules.

Extract visitor IP addresses from NGINX or Apache access logs.

Yes! It specifically validates numbers from 0 to 255 (25[0-5]|2[0-4]\d|[01]?\d\d?).

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