ISO 3166-1 Reference

ISO Country Codes — ISO2 & ISO3 Lookup

The complete ISO 3166-1 reference table — all 195 countries, both alpha-2 (2-letter) and alpha-3 (3-letter) codes.

Used in APIs, telecom routing, banking, passports, and international data systems.

ISO 3166-1 alpha-2 codes are used in phone number provisioning APIs, E.164 formatting, carrier routing tables, regulatory compliance filings, and VoIP platform configuration.

  • Alpha-2 (ISO2): two-letter codes like US, GB, DE — used in web APIs, domain names, and phone systems
  • Alpha-3 (ISO3): three-letter codes like USA, GBR, DEU — used in passports, banking (SWIFT), and UN systems
  • All 195 countries covered with region classification
  • Searchable and filterable by region: Africa, Americas, Asia, Europe, Middle East, Oceania
  • Copy any code instantly with one click
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What are ISO country codes?

ISO 3166-1 is the international standard maintained by the International Organization for Standardization (ISO) that defines short codes for countries, dependent territories, and special areas of geographical interest.

Alpha-2 codes (ISO2) are the most widely used format. You'll find them in internet country-code top-level domains (ccTLDs like .us, .gb, .de), currency codes, phone number APIs, and virtually every web service that handles international data.

Alpha-3 codes (ISO3) are three-letter codes used in machine-readable passports, SWIFT/BIC bank codes, UN statistical databases, and some regulatory filings.

ISO country codes in telecom and VoIP

  • Phone number provisioning APIs — pass the ISO2 code to specify the country
  • E.164 number formatting and validation
  • Carrier routing tables and geo-permission rules
  • Regulatory compliance filings
  • VoIP platform configuration
  • Number porting requests

Frequently asked questions

  • What is ISO2 for United States? — US (ISO3: USA)
  • What is ISO2 for United Kingdom? — GB (ISO3: GBR)
  • What is ISO2 for Germany? — DE (ISO3: DEU)
  • What is ISO2 for Australia? — AU (ISO3: AUS)
  • What is ISO2 for Canada? — CA (ISO3: CAN)
  • What is the difference between ISO2 and ISO3? — ISO2 is two letters, ISO3 is three letters. Both are part of ISO 3166-1.