This is a comparison of the IOC, FIFA, and ISO 3166-1 three-letter codes, combined into one table for easy reference. Highlighted rows indicate those entries in which the three-letter codes differ from column to column. The last column indicates the number of codes present followed by letters to indicate which codes are present (O for Olympic, F for FIFA, and I for ISO) and dashes when a code is absent; capital letters indicate codes which match; lower case letters indicate codes which differ.
Currently, the only ambiguous trigraph between IOC, FIFA and ISO codes is:
Historically, ambiguous trigraphs include:
In the following cases, a code for a historical country or territory matches a modern code of the country it merged into:
Including other lists of country three-letter-codes increases the number of ambiguities. For example:
This list only includes nations or territories that have been assigned at least one of these three types of country codes. For a more complete list of countries, see list of countries.
Codes are shown with their last year of use.