Regex Editor & Tester

This regular expression matches date prefixes for the fourth quarter of the year 2019, specifically October, November, and December. It supports both slash-separated formats (e.g., 2019/10/) and hyphen-separated formats (e.g., 2019-10-) up to the month level. You can use this pattern to filter log files, extract time-sensitive data, or isolate records generated during late 2019.