The ISO Date Format
by Peter Meyer


It is well known that currently dates (in the Gregorian calendar) are expressed in several different ways in various countries. For example what the British write as "8/3/96" the Americans write as "3/8/96" and the Swiss as "8.3.96" or "08.03.96". As daily life becomes more internationalized (and web users quickly note that information is available from all parts of the globe) one may find oneself reading documents in which different date formats are used even though the documents are in the same language. When one reads that something occurred on "3/8/96" one may be left wondering whether it occurred in March or in August. Life would be slightly easier if dates were expressed in a common format.

A numerically-expressed date (in all commonly-used calendar systems) is an expression consisting primarily of a sequence of three numbers specifying year, month and day. There are several components to the manner in which a date may be expressed, but the main ones are:

Almost everywhere in this web site dates are expressed in the format which has been proposed by the International Standards Organization (ISO 8601). With regard to the four components mentioned above, this date format is as follows:

The ISO date format may be used both with the Gregorian and with the Julian systems (and with many other calendar systems). Dates in the Julian calendar are marked with "J", and those in the Gregorian calendar (when this is made explicit) are marked with "G". Dates not identified as to calendar are normally Gregorian.


See also:



Email
Index
Home Page

Last modified: 1998-08-18 G