Regex Tester & Validator

This regex matches lines containing an uppercase three-letter month abbreviation (JAN-DEC), a weekday abbreviation (MON-SUN), and a four-digit year from 1900-2099, all separated by spaces. Because it is anchored with ^ and $ under the multiline flag, each line in a larger text block is validated independently. It is useful for parsing mainframe-style date exports, log files, or fixed-format date stamps like ' JAN MON 2024 '.