Regex Tester & Validator

This regex matches identifiers consisting of exactly two non-digit characters optionally preceded by 3-4 digits and/or followed by 3-4 digits, with optional whitespace separators. With the global, case-insensitive, and multiline flags enabled, it can find patterns like 'AB1234', '1234CD', or '1234 EF 5678' throughout a text. This appears designed for parsing yard stay or logistics codes that combine letter pairs with numeric segments.