YYYYMMDD

YYYYMMDD is a date notation that encodes a calendar date as a concatenation of four-digit year, two-digit month, and two-digit day, with no separators. For example, 20240716 represents July 16, 2024. This compact form is widely used in computing environments for file names, version identifiers, and log entries where separators are undesirable or where easy string-based sorting is needed.

One key advantage is that the numeric string sorts lexicographically in ascending order, which aligns with chronological order. It is also language- and locale-neutral, reducing ambiguity compared with formats that place day and month in different orders. The compact form makes it suitable for systems that require fixed-width identifiers or compact storage.

Limitations and considerations include that the format is not always human-friendly at a glance, especially for those unfamiliar with the convention. It requires fixed width with zero-padding, and some systems treat the value as text rather than a date, which can limit date arithmetic. When combining date information with time, an explicit time component or a standard delimiter is typically added (for example, using ISO 8601 styles such as a separator or an accompanying time stamp).

In contexts where clarity and international readability are priorities, the hyphenated ISO 8601 format YYYY-MM-DD is often preferred. The YYYYMMDD form remains common in filenames, deterministic naming schemes, and databases where fixed-length, sortable identifiers are advantageous.