ISO 3166 Country Codes – Alpha-2, Alpha-3 & Numeric Codes Explained
ISO 3166 Country Codes – Information & Resources
This page provides an overview of ISO 3166 country codes, including the two-letter (alpha-2), three-letter (alpha-3) and numeric country code formats used worldwide in shipping, payments, IT systems, travel, and international data exchange. The links below connect to official and primary reference resources where you can verify country codes and learn more about how ISO 3166 is maintained.
What Is ISO 3166?
ISO 3166 is an international standard that defines codes for the names of countries, dependent territories and special areas of geographical interest. It is published by the International Organization for Standardization (ISO), a global body that develops voluntary standards to support trade, safety, interoperability and data consistency.
ISO 3166 is structured in three main parts:
- ISO 3166-1 – country codes (alpha-2, alpha-3 and numeric)
- ISO 3166-2 – principal subdivisions, such as states or provinces
- ISO 3166-3 – codes for countries that have changed names or no longer exist
The most widely used section in everyday systems is ISO 3166-1, especially the two-letter (alpha-2) and three-letter (alpha-3) country codes.
Official & Primary ISO 3166 Country Code Resources
- ISO.org – ISO 3166 Country Codes Overview – Official introduction to ISO 3166, including links to the standard and general information on country codes.
- ISO Online Browsing Platform – Country Codes Search – Searchable interface for ISO 3166 codes, including alpha-2, alpha-3 and numeric identifiers.
- ISO – Country Names and Code Elements – Information about the structure, maintenance and update process for ISO 3166-1 country codes.
- ISO – Technical Details on ISO 3166 – Background on the technical aspects, working groups and maintenance agencies.
Common ISO 3166-1 Country Codes (Examples)
Below are selected examples of ISO 3166-1 country codes. This is not a complete list and may change over time. Always refer to ISO’s official resources or other primary data providers when you need to confirm codes for production, legal, financial or safety-critical use.
| Country / Territory | Alpha-2 Code | Alpha-3 Code | Numeric Code |
|---|---|---|---|
| Australia | AU |
AUS |
036 |
| New Zealand | NZ |
NZL |
554 |
| Singapore | SG |
SGP |
702 |
| United States of America | US |
USA |
840 |
| Canada | CA |
CAN |
124 |
| United Kingdom | GB |
GBR |
826 |
| Germany | DE |
DEU |
276 |
| India | IN |
IND |
356 |
| Japan | JP |
JPN |
392 |
| Brazil | BR |
BRA |
076 |
Note: This table is a sample only and does not list all ISO 3166-1 country codes. For complete and up-to-date information, always refer to official ISO resources or other primary data providers.
How ISO 3166 Country Codes Are Used
ISO 3166 country codes appear in many everyday systems and online tools, including:
- Websites & E-commerce: country selectors, shipping destinations, localisation settings.
- Payments & Finance: card issuing country, cross-border reporting and compliance.
- Travel & Aviation: reservation systems, ticketing, passenger data and baggage tags.
- IT & Databases: storing country information in a consistent, machine-readable format.
- Statistics & Reporting: global trade data, population reports and comparative studies.
Using standardised ISO 3166 codes helps reduce confusion, avoid spelling differences and ensure that systems from different countries can exchange data reliably.
Related Standards & Helpful Links
- Currency Codes – ISO 4217: Many currency codes are derived from the alpha-2 or alpha-3 country codes defined in ISO 3166-1. See your dedicated currency page for more details.
- Language Codes – ISO 639: Often used alongside ISO 3166 in localisation and translation systems.
- Time Zones – ISO-Compatible Formats: Time zone data and “time in city / country” pages frequently use ISO codes as identifiers in URLs and APIs.
Important Disclaimer
This page is provided for general information and educational purposes only. It does not reproduce or replace the official ISO 3166 standard, and it does not create, maintain or update any country code data. While care is taken to keep the information on this page reasonable and consistent, codes, country names and classifications can change over time.
For authoritative, complete and up-to-date ISO 3166 country codes, always refer to:
- Official publications and tools provided by the International Organization for Standardization (ISO)
- Other trusted standards bodies, regulators or professional data providers
Do not rely on this page alone for decisions involving regulatory compliance, legal obligations, safety, financial reporting or other critical business processes.