Regex Tester & Validator

PCRE pattern that matches WebVTT cue timing lines such as `00:01.000 --> 00:05.500` or `01:02:03.400 --> 01:02:08.000`. It uses an (?(DEFINE)) block to define reusable subpatterns for hours (00-29), minutes/seconds (00-59), milliseconds (000-999), and a full timecode, then captures the start and end timestamps in named groups. Useful for parsing subtitle files, extracting cue boundaries, or validating VTT timing syntax, with trailing cue settings captured as well.