Time and Date Formats

ISO Date format

I have switched to the international standard (ISO) date format. This format is described in numerous locations (see the links side bar) but just to be redundant, I'll briefly describe it here.

year-month-dayThours:minutes+offset
Note, the T is literal, so this web page was created at
2005-01-13T07:02-0600
Now, obviously most people don't bother putting in the time and thus do not need the T or anything after it. Also note that the offset may be superfluous for some cases. The last modified date stamp on this page reflects the more common usage.

Isn't that only used by the military?

Not at all. Computers are one of the most common cases where a more international date and time format is used. Outside the US, it is very common to find cultures that do not regularly use two twelve hour periods to indicate a day, but instead use a single twenty four hour period.

Why not use the normal American format?

I find the US format to be bizzare at best, incomprehensible at worst. It also does not match what I find routinely used on the computers with which I work regularly. The format also has the advantage of being almost instantly recognizable and readable by Americans and Europeans. Europeans will notice that the year is first which is distinctive to the ISO format. Americans will be comfortable with the fact that the month precedes the day, which is what they are used to. As the year is always written out with all four digits, this makes it easier to recognize what is the year and what is not.


Last modified 2005-04-10
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