List of IOC country codes

The International Olympic Committee (IOC) uses three-letter abbreviation country codes to refer to each group of athletes that participate in the Olympic Games. Each code usually identifies a National Olympic Committee (NOC), but there are several codes that have been used for other instances in past Games, such as teams composed of athletes from multiple nations, or groups of athletes not formally representing any nation.

Several of the IOC codes are different from the standard ISO 3166-1 alpha-3 codes. Other sporting organisations, such as FIFA, use similar country codes to refer to their respective teams, but with some differences. Still others, such as the Commonwealth Games Federation or Association of Tennis Professionals, use the IOC list verbatim.

The 1956 Winter Olympics and 1960 Summer Olympics were the first Games to feature Initials of Nations to refer to each NOC in the published official reports. However, the codes used at the next few Games were often based on the host nation's language (e.g., GIA for Japan at the 1956 Winter Olympics and 1960 Summer Olympics, both held in Italy, from Italian Giappone) or based on the French name for the nation (e.g., COR for Korea, from Corée). By the 1972 Winter Olympics, most codes were standardized on the current usage, but several have changed in recent years. Additionally, the dissolution of the Soviet Union, division and unification of Germany, breakup of Yugoslavia, dissolution of Czechoslovakia, and several other instances of geographical renaming have all resulted in code changes.

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