Regex Editor & Tester

This regular expression is designed to match IPv4 addresses followed by a Classless Inter-Domain Routing (CIDR) subnet mask, such as `192.168.1.0/24`. It validates four octets (0-255) and a subnet prefix length from 0 to 32. Due to its grouping, it technically allows either a dot or a slash before the prefix, but it is primarily intended for networking configuration forms, firewall rule validation, or any application validating network IP ranges.