ISO 3166-1

ISO 3166-1 is part of the ISO 3166 standard published by the International Organization for Standardization (ISO), and defines codes for the names of countries, dependent territories, and special areas of geographical interest. The official name of the standard is Codes for the representation of names of countries and their subdivisions – Part 1: Country codes. It defines three sets of country codes:

The alphabetic country codes were first included in ISO 3166 in 1974, and the numeric country codes were first included in 1981. The country codes have been published as ISO 3166-1 since 1997, when ISO 3166 was expanded into three parts, with ISO 3166-2 defining codes for subdivisions and ISO 3166-3 defining codes for former countries.

As a widely used international standard, ISO 3166-1 is implemented in other standards and used by international organizations to allow facilitation of the exchange of goods and information. However, it is not the only standard for country codes. Other country codes used by many international organizations are partly or totally incompatible with ISO 3166-1, although some of them closely correspond to ISO 3166-1 codes.

Currently 249 countries, territories, or areas of geographical interest are assigned official codes in ISO 3166-1. According to the ISO 3166 Maintenance Agency (ISO 3166/MA), the only way to enter a new country name into ISO 3166-1 is to have it registered in one of the following two sources:

To be listed in the bulletin Country Names, a country must be at least one of the following:

The list of names in Country and Region Codes for Statistical Use of the UN Statistics Division is based on the bulletin Country Names and other UN sources.

Once a country name or territory name appears in either of these two sources, it will be added to ISO 3166-1 by default.

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