Polite Notice: this implementation is not yet ready for production environments. See Status for more info.

In December 2012, ECMA International published the first edition of Standard ECMA-402, better known as the ECMAScript Internationalization API. This specification provides the framework to bring long overdue localisation methods to ECMAScript implementations.

Google have an implementation of this API that is available in recent versions of V8 and Chrome/Chromium 24 and later. Mozilla also have a working implementation in the current Firefox nightly builds.

Intl.js attempts to fill the void of availability for this API. It will provide the framework as described by the specification, so that developers can take advantage of the native API in environments that support it, or Intl.js for legacy or unsupporting environments.

Intl.js isn't yet ready for production environments. Current progress is as follows:

• All internal methods except for some that are implementation dependent
• Checking structural validity of language tags
• Canonicalizing the case and order of language subtags
• Intl.NumberFormat
  • The Intl.NumberFormat constructor (11.1)
  • Properties of the Intl.NumberFormat Constructor (11.2)
  • Properties of the Intl.NumberFormat Prototype Object (11.3)
  • Properties of Intl.NumberFormat Instances(11.4)
• Intl.DateTimeFormat
  • The Intl.DateTimeFormat constructor (12.1)
  • Properties of the Intl.DateTimeFormat Constructor (12.2)
  • Properties of the Intl.DateTimeFormat Prototype Object (12.3)
  • Properties of Intl.DateTimeFormat Instances(12.4)
• Locale Sensitive Functions of the ECMAScript Language Specification
  • Properties of the Number Prototype Object (13.2)
  • Properties of the Date prototype object (13.3)

• Canonicalizing language tags containing subtags that have a "Preferred-value" from the IANA Language Subtag registry
• BestFitSupportedLocales internal function
• Implementation-dependent numbering system mappings
• Collator objects (Intl.Collator)
• Properties of the String prototype object
• Test suites

None of the implementation has been tested for compliance as of yet, and a few of the implemented functions may currently be non-conforming and/or incomplete. Those functions have comments marked as 'TODO' in the source code. test402 integration is planned.

Intl.js is designed to be compatible with ECMAScript 3.1 environments in order to follow the specification as closely as possible. However, some consideration is given to legacy (ES3) environments, and the goal of this project is to at least provide a working, albeit non-compliant implementation where ES5 methods are unavailable.

The main Intl.js file contains no locale data itself. Instead, the data should be provided, parsed into a JavaScript object, using the Intl.__addLocaleData() method.

Intl.js uses the Unicode CLDR locale data, as recommended by the specification. Some of the data from CLDR version 22.1 is currently available in JSON and JSONP formats in the locale-data folder of this repository.

Work is in progress to convert the 23.1 data to JSON format. The tools folder contains a Node.js script that automates the process to extract only the data needed by Intl.js. However, the script doesn't support converting the collation data to JSON (yet), and some of the localisation data in the version 22.1 files appears to be missing from the 23.1 data.