International Date Format

2021 Apr 14, Timid Robot Zehta

Please use the international date format

Please consider using the international date format (ex. 2021-04-14 or YYYY-MM-DD) instead of a local date format (ex. 4/14/2021 or D/MM/YYYY).

The international date format is not only unambiguous and easier to sort, it participates in internationalism instead of contributing to colonization, imperialism, and nationalism.

While it may be less intuitive in regional contexts, it is an educational opportunity requiring relatively low effort.


"xkcd: ISO 8601" by Randall Munroe is licensed under CC-BY-NC 2.5

"xkcd: ISO 8601" by Randall Munroe is licensed under CC-BY-NC 2.5.

For an explanation of the comic (ex. the meaning of the dates in the gray area), see 1179: ISO 8601 - explain xkcd.


The international date format is defined by the International Organization for Standardization (ISO) in IS 8601 (ISO 8601 - Wikipedia). However, that standards body does not allow open access to the standards!

Thankfully, RFC 3339 - Date and Time on the Internet: Timestamps is available (in addition to the descriptions in the Wikipedia article above).

The World Wide Web Consortium (W3C) discusses the pros and cons of the international date format here: Date formats.