International standard ISO 5218 defines a representation of human sexes through a language-neutral single-digit code. It can be used in information systems such as database applications. This article is about computing. ...

The four codes specified in ISO 5218 are:

• 0 = not known,
• 1 = male,
• 2 = female,
• 9 = not applicable.

The standard specifies that its use may be referred to by the designator "SEX".

The standard explicitly states that no significance is to be placed on the fact that male is encoded as 1 and female as 2. The encoding merely reflects existing practice in the countries that initiated this standard.

ISO 5218 was created by ISO's Data Management and Interchange Technical Committee and proposed in November 1976, and updated in July 2004. This article does not cite any references or sources. ... Year 1976 Pick up sticks(MCMLXXVI) was a leap year starting on Thursday (link will display full calendar) of the Gregorian calendar. ... Year 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ...

This standard is used in several national identification numbers. For example, the first digit of the French INSEE number, the first digit of the Republic of China national identification card (Chinese: 中華民國國民身分證) and the first digit of so called Personal Number that was in use until 1991 in Hungary all use ISO 5218 values. A national identification number is used by the governments of many countries as a means of tracking their citizens, permanent residents, and temporary residents for the purposes of work, taxation, government benefits, health care, and other governmentally-related functions. ... INSEE is the French abbreviation for the French National Institute for Statistics and Economic Studies (French: Institut National de la Statistique et des Études Économiques). ... For the Chinese civilization, see China. ...