YYYYMMDDTHHmmssZ

YYYYMMDDTHHmmssZ is a timestamp pattern used to encode a specific moment in Coordinated Universal Time (UTC). It is a compact variant of ISO 8601 date-time representations, consisting of fixed-width fields: year (YYYY), month (MM), day (DD), the literal T as a separator, hour (HH), minute (mm), second (ss), and a trailing Z indicating zero offset from UTC.

An example of the format is 20240507T123045Z, which corresponds to May 7, 2024 at 12:30:45 UTC. The string has a consistent length, typically 18 characters, and uses only digits along with the T and Z separators.

One key property of this format is its lexical sort order. Because the components are arranged from most significant to least significant (year to second) and use fixed widths, lexicographic ordering of these strings matches chronological ordering. This makes the pattern convenient for filename conventions, log entries, and data interchange where compactness and straightforward sorting are beneficial.

Common uses include generating compact timestamps for file names, log records, and identifiers in systems that require UTC representation without locale-specific separators. While it improves compactness and portability, the format is less human-friendly than its extended ISO 8601 counterparts (which use hyphens and colons) and does not natively express fractional seconds or time-zone offsets other than UTC. When needed, fractional seconds or alternative offsets must be added with additional notation.