Intl.NumberFormat

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The Intl.NumberFormat object is a constructor for objects that enable language sensitive number formatting.

Syntax

new Intl.NumberFormat([locales[, options]])
Intl.NumberFormat.call(this[, locales[, options]])

Parameters

locales

Optional. A string with a BCP 47 language tag, or an array of such strings. For the general form and interpretation of the locales argument, see the Intl page. The following Unicode extension key is allowed:

nu
The numbering system to be used. Possible values include: "arab", "arabext", "bali", "beng", "deva", "fullwide", "gujr", "guru", "hanidec", "khmr", "knda", "laoo", "latn", "limb", "mlym", "mong", "mymr", "orya", "tamldec", "telu", "thai", "tibt".
options

Optional. An object with some or all of the following properties:

localeMatcher
The locale matching algorithm to use. Possible values are "lookup" and "best fit"; the default is "best fit". For information about this option, see the Intl page.
style
The formatting style to use. Possible values are "decimal" for plain number formatting, "currency" for currency formatting, and "percent" for percent formatting; the default is "decimal".
currency
The currency to use in currency formatting. Possible values are the ISO 4217 currency codes, such as "USD" for the US dollar, "EUR" for the euro, or "CNY" for the Chinese RMB — see the Current currency & funds code list. There is no default value; if the style is "currency", the currency property must be provided.
currencyDisplay
How to display the currency in currency formatting. Possible values are "symbol" to use a localized currency symbol such as €, "code" to use the ISO currency code, "name" to use a localized currency name such as "dollar"; the default is "symbol".
useGrouping
Whether to use grouping separators, such as thousands separators or thousand/lakh/crore separators. Possible values are true and false; the default is true.

The following properties fall into two groups: minimumIntegerDigits, minimumFractionDigits, and maximumFractionDigits in one group, minimumSignificantDigits and maximumSignificantDigits in the other. If at least one property from the second group is defined, then the first group is ignored.

minimumIntegerDigits
The minimum number of integer digits to use. Possible values are from 1 to 21; the default is 1.
minimumFractionDigits
The minimum number of fraction digits to use. Possible values are from 0 to 20; the default for plain number and percent formatting is 0; the default for currency formatting is the number of minor unit digits provided by the ISO 4217 currency code list (2 if the list doesn't provide that information).
maximumFractionDigits
The maximum number of fraction digits to use. Possible values are from 0 to 20; the default for plain number formatting is the larger of minimumFractionDigits and 3; the default for currency formatting is the larger of minimumFractionDigits and the number of minor unit digits provided by the ISO 4217 currency code list (2 if the list doesn't provide that information); the default for percent formatting is the larger of minimumFractionDigits and 0.
minimumSignificantDigits
The minimum number of significant digits to use. Possible values are from 1 to 21; the default is 1.
maximumSignificantDigits
The maximum number of significant digits to use. Possible values are from 1 to 21; the default is minimumSignificantDigits.

Description

Properties

Intl.NumberFormat.prototype
Allows the addition of properties to all objects.

Methods

Intl.NumberFormat.supportedLocalesOf()
Returns an array containing those of the provided locales that are supported without having to fall back to the runtime's default locale.

NumberFormat instances

Properties

NumberFormat instances inherit the following properties from their prototype:

Intl.NumberFormat.prototype.constructor
A reference to Intl.NumberFormat.
Intl.NumberFormat.prototype.format
Getter; returns a function that formats a number according to the locale and formatting options of this NumberFormat object.

Methods

NumberFormat instances inherit the following methods from their prototype:

Intl.NumberFormat.prototype.resolvedOptions()
Returns a new object with properties reflecting the locale and collation options computed during initialization of the object.

Examples

Basic usage

In basic use without specifying a locale, a formatted string in the default locale and with default options is returned.

var number = 3500;

console.log(new Intl.NumberFormat().format(number));
// → '3,500' if in US English locale

Using locales

This example shows some of the variations in localized number formats. In order to get the format of the language used in the user interface of your application, make sure to specify that language (and possibly some fallback languages) using the locales argument:

var number = 123456.789;

// German uses comma as decimal separator and period for thousands
console.log(new Intl.NumberFormat('de-DE').format(number));
// → 123.456,789

// Arabic in most Arabic speaking countries uses real Arabic digits
console.log(new Intl.NumberFormat('ar-EG').format(number));
// → ١٢٣٤٥٦٫٧٨٩

// India uses thousands/lakh/crore separators
console.log(new Intl.NumberFormat('en-IN').format(number));
// → 1,23,456.789

// the nu extension key requests a numbering system, e.g. Chinese decimal
console.log(new Intl.NumberFormat('zh-Hans-CN-u-nu-hanidec').format(number));
// → 一二三,四五六.七八九

// when requesting a language that may not be supported, such as
// Balinese, include a fallback language, in this case Indonesian
console.log(new Intl.NumberFormat(['ban', 'id']).format(number));
// → 123.456,789

Using options

The results can be customized using the options argument:

var number = 123456.789;

// request a currency format
console.log(new Intl.NumberFormat('de-DE', { style: 'currency', currency: 'EUR' }).format(number));
// → 123.456,79 €

// the Japanese yen doesn't use a minor unit
console.log(new Intl.NumberFormat('ja-JP', { style: 'currency', currency: 'JPY' }).format(number));
// → ¥123,457

// limit to three significant digits
console.log(new Intl.NumberFormat('en-IN', { maximumSignificantDigits: 3 }).format(number));
// → 1,23,000

Specifications

Specification Status Comment
ECMAScript Internationalization API 1.0 (ECMA-402)
The definition of 'Intl.NumberFormat' in that specification.
Standard Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 24 29 (29) 11 15 Not supported
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support Not supported 26 Not supported Not supported Not supported Not supported

See also

Document Tags and Contributors

Contributors to this page: fscholz, Mingun, Sheppy, Norbert
Last updated by: fscholz,