Intl.Locale() constructor - JavaScript | MDN

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Intl.Locale() constructor

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2020.

The Intl.Locale() constructor creates Intl.Locale objects.

Try it

const korean = new Intl.Locale("ko", {
  script: "Kore",
  region: "KR",
  hourCycle: "h23",
  calendar: "gregory",
});

const japanese = new Intl.Locale("ja-Jpan-JP-u-ca-japanese-hc-h12");

console.log(korean.baseName, japanese.baseName);
// Expected output: "ko-Kore-KR" "ja-Jpan-JP"

console.log(korean.hourCycle, japanese.hourCycle);
// Expected output: "h23" "h12"

Syntax

js
new Intl.Locale(tag)
new Intl.Locale(tag, options)

Note: Intl.Locale() can only be constructed with new. Attempting to call it without new throws a TypeError.

The Unicode locale identifier string. For the syntax of locale identifier strings, see the Intl main page. Note that the Intl.Locale constructor, unlike most other Intl constructors, does not accept an array of locales or undefined.

options

An object that contains configuration for the Locale. Option values here take priority over extension keys in the locale identifier. Possible properties are:

language

The language. Any syntactically valid string following the unicode_language_subtag grammar (2–3 or 5–8 letters) is accepted, but the implementation only recognizes certain kinds.

script

The script. Any syntactically valid string following the unicode_script_subtag grammar (4 letters) is accepted, but the implementation only recognizes certain kinds.

region

The region. Any syntactically valid string following the unicode_region_subtag grammar (either 2 letters or 3 digits) is accepted, but the implementation only recognizes certain kinds.

variants

The variants. It should be a dash (-) separated list of unique variant tags, where each tag is any syntactically valid string following the unicode_variant_subtag grammar (either 5–8 alphanumerals or a digit followed by 3 alphanumerals), but the implementation only recognizes certain kinds.

calendar

The calendar. Any syntactically valid string following the type grammar (one or more segments of 3–8 alphanumerals, joined by hyphens) is accepted, but the implementation only recognizes certain kinds, which are listed in Intl.supportedValuesOf().

collation

The collation. Any syntactically valid string following the type grammar is accepted, but the implementation only recognizes certain kinds, which are listed in Intl.supportedValuesOf().

numberingSystem

The numbering system. Any syntactically valid string following the type grammar is accepted, but the implementation only recognizes certain kinds, which are listed in Intl.supportedValuesOf().

caseFirst

The case-first sort option. Possible values are "upper", "lower", or "false".

hourCycle

The hour cycle. Possible values are "h23", "h12", "h11", or the practically unused "h24", which are explained in Intl.Locale.prototype.getHourCycles

numeric

The numeric sort option. A boolean.

Examples

Basic usage

At its very simplest, the Intl.Locale() constructor takes a locale identifier string as its argument:

const us = new Intl.Locale("en-US");

Using the Locale constructor with an options object

The constructor also takes an optional configuration object argument, which can contain any of several extension types. For example, set the hourCycle property of the configuration object to your desired hour cycle type, and then pass it into the constructor:

js
const locale = new Intl.Locale("en-US", { hourCycle: "h12" });
console.log(locale.hourCycle); // "h12"

Specifications

Specification

ECMAScript® 2027 Internationalization API Specification
# sec-intl-locale-constructor

Browser compatibility

Enable JavaScript to view this browser compatibility table.

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Standard built-in objects
Intl.Locale
Constructor
1. Intl.Locale()
Instance methods
1. getCalendars()
2. getCollations()
3. getHourCycles()
4. getNumberingSystems()
5. getTextInfo()
6. getTimeZones()
7. getWeekInfo()
8. maximize()
9. minimize()
10. toString()
Instance properties
1. baseName
2. calendar
3. caseFirst
4. collation
5. hourCycle
6. language
7. numberingSystem
8. numeric
9. region
10. script
11. variants
Inheritance
Object/Function
Static methods
1. apply()
2. bind()
3. call()
4. toString()
5. [Symbol.hasInstance]()
Static properties
1. displayName
2. length
3. name
4. prototype
5. arguments
6. caller
Instance methods
1. __defineGetter__()
2. __defineSetter__()
3. __lookupGetter__()
4. __lookupSetter__()
5. hasOwnProperty()
6. isPrototypeOf()
7. propertyIsEnumerable()
8. toLocaleString()
9. toString()
10. valueOf()
Instance properties
1. __proto__
2. constructor
Related pages
Intl
Intl.Collator
Intl.DateTimeFormat
Intl.DisplayNames
Intl.DurationFormat
Intl.ListFormat
Intl.NumberFormat
Intl.PluralRules
Intl.RelativeTimeFormat
Intl.Segmenter