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Is there an international standard for specifying dates? © iStock

Is there an international standard for specifying dates?

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With worldwide networks ever expanding we should probably begin by agreeing on which day it is.

Asked by: J Fairlamb, Berkwick upon Tweed


There is a global standard - step forward ISO 8601.

ISO stands for the International Organisation for Standardisation. Its member states hammer out standards on everything from the characteristics of the oil from oranges used in perfume, to the average ground contact pressure for industrial diggers.

ISO 8601 sets out an internationally agreed way of expressing dates in the Gregorian calendar, the dating system used in most of the developed world. At its most basic, ISO 8601 stipulates that date and time information is written with the most significant first and least significant last. In other words, you start with the year, then the month, then the day. So, 1 July 2005 would be written 2005-07-01.

ISO feels strongly that the standard should be used as widely as possible. On its website it urges that should any of us turn up for a flight or a train on the wrong day, we should demand to know why ISO 8601 is not being used.


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