User:Omegatron/Date formatting/Language codes

If we were to determine the user's preferred date format based on their browser's preferred language codes, how reliable would this be? What language tags/country codes would map to what?

Date formatting is essentially a feature of language, so this would be an appropriate use of the tags. en-us always formats as mm/dd/yyyy, while en-gb always formats as dd/mm/yyyy, for instance.


 * W3C: FAQ: Accept-Language used for locale setting
 * Date and time localization based on browser headers - Sosius website

(Based on Calendar date and the list here)

January 15, 2001

 * en (since most visitors are American?)
 * en-us
 * en-ca
 * fr-ca

15 January 2001

 * en-au
 * en-gb
 * en-ie
 * en-za
 * bg
 * de
 * de-ch
 * el
 * es
 * es-mx
 * fr
 * fr-ch
 * he
 * hi
 * in
 * it
 * nl
 * nl-be
 * pl
 * pt-br
 * ro
 * sl
 * sv
 * th

2001-01-15
???