06-26-99, 26-06-99, 1999-06-26

For computer-related stuff where filenames were once severely limited in length, I used to use YYMDD, and more recently YYYYMDD. The month is compressed to one letter by making it base-13 (no zero, though) and using A, B, and C for 10, 11, and 12. Thus, Halloween this year is 1999A31 and U.S. Independence Day is 1999704.

The nice thing is that (at least in the ASCII character set) the letters come after the numbers when electronically sorting, so dates are properly sorted in year order, then month, then day.

As for people-readable, I’ve preferred “1999-August-30” or “1999-Aug-30” so there’s never the possibility of confusing the month with the day. The English-language problems are apparent which, oddly, the short abbreviation form above fixes: if we went with YYYY-M-DD and used base-13, there would never be a day-month mixup.

Oh, and the 99-VIII-30 format is a neat idea (although a little clumsy) until a couple years from now when 01-II-03 could be 2001-February-3 or 2003-February-1.

The hyphens are there because normal human beings cannot read eight-digit unpunctuated numbers reliably.


John W. Kennedy
“Compact is becoming contract; man only earns and pays.”
– Charles Williams

Not to mention the fact that people can not be relied upon to insert the place holders. Example, 19990627, or 1999627, it is clearer to use 1999-06-27, 1999-6-27. As for whether we need a unversal format, I imagine there is one to an extent. While in common speach it dosn’t apply, I imagine that most international companies and multinational organization (NATO, UN, OPEC) have a consistant method for doing things. Now consistancy between these several methods is unlikely, but you need a primer to sort the languages, it isn’t unbelievable to use it to sort the dates as well. When Esperanto gets moving then we can push towards a universal yyyy-mm-dd system.

I wonder this, is the US the only odd ball? I know the US and UK flip the month and year, someone mentioned that Canada (or at least the French section) do as well, but many know that China uses a total unrelated calander (I assume they conform to us for international purposes). Some religious states use their own calendar based on biblical (or whatever) texts, so they offer a much more confusing situation. Does anyone have first hand expierence with the commonality of the mm-dd-yyyy, and dd-mm-yyyy methods, I even bet that there is a country or two that already use the yyyy-mm-dd method? any thing to offer?


The facts expressed here belong to everybody, the opinions to me. The distinction is
yours to draw…

Omniscient; BAG

Thats supposed to read US and UK flip the month and day…

Leaving aside the question of how computers store dates, there’s bound to be a dozen or more years (2001 - 2012) of total confusion regarding written dates such as 03/04/01.

I guess we at the US Patent & Trademark Office aren’t normal human beings. Our computer system uses MMDDYYYY.


“Age is mind over matter; if you don’t mind, it don’t matter.” -Leroy “Satchel” Paige

Haven’t gotten rid of the old 1401 yet?


John W. Kennedy
“Compact is becoming contract; man only earns and pays.”
– Charles Williams