Regex Tester & Validator

This regular expression matches an extended ISO 8601 date and time string. It captures dates between the years 1900 and 2099, followed by a 'T' separator, standard time in HH:MM:SS format, optional fractional seconds, and an optional timezone offset like +HH:MM or 'Z' for UTC. It is highly useful for parsing log files, validating API payloads, and extracting timestamps from structured text documents where precise temporal data is required.