FW: Time Zone Codes

Paul Eggert eggert at twinsun.com
Wed May 17 19:44:50 UTC 2000

   From:	Spencer, Denis [OCDFR] [SMTP:dspencer at ocdfr.jnj.com]
   Sent:	Wednesday, May 17, 2000 5:07 AM

   Are there any standards (like ISAO country codes) for time zones?

There is a standard for numeric codes: ISO 8601.  It allows several
representations, e.g. "+0100" or "+01" or "+01:00" for Central
European Time.  "+0100" seems the most popular, as it also conforms to
Internet RFC 822.  It also allows "Z" for UTC.

There is no standard for traditional alphabetic codes.  They are
ambiguous in practice, and fixing this would be more of a political
mess than it's worth.  Just try telling the Australians that "EST" is
taken by the US, or telling the Israelis that India owns "IST"!

   eg we use GMT = Greenwich Mean Time
   CTE = Central European Time

Surely you meant "CET"?

   But we need others.

You can look in the tz database for the abbreviations that it uses,
but they are not official (and in many cases are my own invention).
At one point Vic Abell <abe at purdue.edu> was maintaining a more
extensive list that he gleaned partly from email headers, but I don't
know what its current status is.  GNU getdate (available as part of
the GNU C library) also has a list.

For more about ISO 8601 and the tz database, please see:


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