Regex Tester & Validator

Validates IPv4 addresses by ensuring each of the four octets falls within the valid range of 0-255. It uses a clever combination of alternatives to match numbers 250-255, 200-249, 100-199, 10-99, and 0-9. The negative lookahead (?!$) ensures dots only appear between octets, not at the end. This is a compact solution for validating IP addresses in network configuration, log parsing, or form validation scenarios.