Regex Editor & Tester

This regex matches ISO 8601 formatted datetime strings in UTC timezone with milliseconds. It validates the format YYYY-MM-DDTHH:MM:SS.sssZ, requiring exactly 4-digit years, 2-digit date/time components, and exactly 3 digits for milliseconds. With the 'gm' flags, it can match multiple datetime occurrences across multiple lines in a text, making it suitable for log parsing and data validation.