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Regex for IPv4 address matching in JavaScript

Q: What is the regex for IPv4 address matching in JavaScript?

(?:\d{1,3}\.){3}\d{1,3} — IPv4 addresses appear constantly in logs and configs. This pattern matches the dotted-quad shape; add range checks for strict 0-255 octets. Try it live below.

IPv4 addresses appear constantly in logs and configs. This pattern matches the dotted-quad shape; add range checks for strict 0-255 octets. Try it live below.

Working example

/(?:\d{1,3}\.){3}\d{1,3}/g

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Describe what to match

/(?:\d{1,3}\.){3}\d{1,3}/gvalid ✓

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