ISO Language Codes – ISO 639-1 & 639-2 Explained

ISO Language Codes – ISO 639 Information & Resources

This page provides an overview of ISO language codes, also known as ISO 639 codes, which are used to identify languages in a standard way across websites, apps, databases, translation systems and technical documentation. The links below connect to official and primary reference resources where you can look up language codes and learn more about how the ISO 639 standard is maintained.

What Is ISO 639?

ISO 639 is an international standard that defines short codes for the names of languages. These codes help software, services and organisations refer to languages consistently, even when people use different spellings or alphabets.

ISO 639 is divided into several parts, including:

  • ISO 639-1 – two-letter language codes (e.g. en, fr, de)
  • ISO 639-2 – three-letter language codes, often used in libraries and metadata
  • ISO 639-3 – three-letter codes covering a much larger set of languages, including many regional and historical languages

The most common format you will see in websites and applications is the ISO 639-1 two-letter code, often combined with a country code (for example en-AU or en-US) in language or locale settings.

Official & Primary ISO 639 Language Code Resources

Common ISO 639-1 Language Codes (Examples)

The table below lists selected examples of ISO 639-1 two-letter language codes. This is not a complete list and may change over time. Always refer to official ISO publications or other primary data providers when you need to confirm codes for production, regulatory or business-critical use.

Language ISO 639-1 Code ISO 639-2 Code (Example)
English en eng
French fr fra (or fre)
German de deu (or ger)
Spanish es spa
Portuguese pt por
Italian it ita
Chinese zh zho (or chi)
Japanese ja jpn
Arabic ar ara
Hindi hi hin

Note: This table is a sample only and does not list all languages or all parts of the ISO 639 standard. Always refer to official ISO resources or other primary data providers for comprehensive and up-to-date code lists.

How ISO Language Codes Are Used

ISO 639 language codes appear in many everyday tools and systems, including:

  • Websites & Apps: language selectors, localisation settings and content translations.
  • Search & SEO: language targets in meta tags and hreflang attributes.
  • Software & APIs: configuration files, headers and data formats for multilingual content.
  • Streaming & Media: audio and subtitle language settings.
  • Data & Analytics: reporting on language usage and localisation coverage.

Using standardised ISO language codes helps keep multilingual systems consistent and reduces ambiguity when multiple languages or regional variants are involved.

Related Standards & Helpful Links

  • Country Codes – ISO 3166: Often combined with ISO 639 language codes to form complete locale identifiers (for example en-AU or fr-CA).
  • Currency Codes – ISO 4217: Three-letter codes (such as AUD, USD, EUR) used alongside language and country codes in many international systems.
  • IETF BCP 47 Language Tags: Defines how language codes, country codes and script codes are combined in internet protocols and web standards.

Important Disclaimer

This page is provided for general information and educational purposes only. It does not reproduce or replace the official ISO 639 standard, and it does not create, maintain or update any language code data. Language codes, names and classifications can change over time as standards are updated.

For authoritative, complete and up-to-date ISO 639 language codes, always refer to:

  • Official resources from the International Organization for Standardization (ISO)
  • Recognised maintenance agencies and standards bodies

Do not rely on this page alone for decisions involving regulatory compliance, legal obligations, safety-critical systems, financial reporting or other core business processes.