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← GalleryIPv4 address with optional CIDR suffix✨ Emoji Combos

/^(?:(?:[1-9]?[0-9]|1[0-9][0-9]|2(?:[0-4][0-9]|5[0-5]))\.){3}(?:[1-9]?[0-9]|1[0-9][0-9]|2(?:[0-4][0-9]|5[0-5]))(?:\/(?:[12]?[0-9]|3[0-2]))?$/JavaScript+12 years ago✓ Pre-loaded

About this regex

Validates an IPv4 address with an optional CIDR routing prefix suffix. Each octet is restricted to 0-255, and if present, the CIDR suffix (after the slash) must be between 0 and 32. Commonly used in networking forms to validate IP/subnet notation like 192.168.1.0/24.

ipv4 cidr network ip-address validation

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