List of ISO 3166 country codes

The International Organization for Standardization (ISO) created and maintains the ISO 3166 standard – Codes for the representation of names of countries and their subdivisions. The ISO 3166 standard contains three parts: ISO 3166-1 – Codes for the representation of names of countries and their subdivisions – Part 1: Country codes defines codes for the names of countries, dependent territories, and special areas of geographical interest.

Source: Wikipedia — List of ISO 3166 country codes (CC BY-SA 4.0)