The Intl.DateTimeFormat() constructor for objects that enable language-sensitive date and time formatting.


new Intl.DateTimeFormat([locales[, options]])


locales Optional

A string with a BCP 47 language tag, or an array of such strings. To use the browser's default locale, pass an empty array. Unicode extension are supported (for example "en-US-u-ca-buddhist"). For the general form and interpretation of the locales argument, see the Intl page. The following Unicode extension keys are allowed:

Numbering system. 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".
Calendar. Possible values include: "buddhist", "chinese", "coptic", "ethiopia", "ethiopic", "gregory", "hebrew", "indian", "islamic", "iso8601", "japanese", "persian", "roc".
Hour cycle. Possible values include: "h11", "h12", "h23", "h24".
options Optional

An object with some or all of the following properties:

The date formatting style to use when calling format(). Possible values include:
  • "full"
  • "long"
  • "medium"
  • "short"
The time formatting style to use when calling format(). Possible values include:
  • "full"
  • "long"
  • "medium"
  • "short"
The number of fractional seconds to apply when calling format(). Valid values are 0-3.
Calendar. Possible values include: "buddhist", "chinese", " coptic", "ethiopia", "ethiopic", "gregory", " hebrew", "indian", "islamic", "iso8601", " japanese", "persian", "roc".
The way day periods should be expressed. Possible values include: "narrow", "short", " long".
Numbering System. 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".
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.
The time zone to use. The only value implementations must recognize is "UTC"; the default is the runtime's default time zone. Implementations may also recognize the time zone names of the IANA time zone database, such as "Asia/Shanghai", "Asia/Kolkata", "America/New_York".
Whether to use 12-hour time (as opposed to 24-hour time). Possible values are true and false; the default is locale dependent. This option overrides the hc language tag and/or the hourCycle option in case both are present.
The hour cycle to use. Possible values are "h11", "h12", "h23", or "h24". This option overrides the hc language tag, if both are present, and the hour12 option takes precedence in case both options have been specified.
The format matching algorithm to use. Possible values are "basic" and "best fit"; the default is "best fit". See the following paragraphs for information about the use of this property.

The following properties describe the date-time components to use in formatted output, and their desired representations. Implementations are required to support at least the following subsets:

  • weekday, year, month, day, hour, minute, second
  • weekday, year, month, day
  • year, month, day
  • year, month
  • month, day
  • hour, minute, second
  • hour, minute

Implementations may support other subsets, and requests will be negotiated against all available subset-representation combinations to find the best match. Two algorithms are available for this negotiation and selected by the formatMatcher property: A fully specified "basic" algorithm and an implementation-dependent "best fit" algorithm.

The representation of the weekday. Possible values are:
  • "long" (e.g., Thursday)
  • "short" (e.g., Thu)
  • "narrow" (e.g., T). Two weekdays may have the same narrow style for some locales (e.g. Tuesday's narrow style is also T).
The representation of the era. Possible values are:
  • "long" (e.g., Anno Domini)
  • "short" (e.g., AD)
  • "narrow" (e.g., A)
The representation of the year. Possible values are:
  • "numeric" (e.g., 2012)
  • "2-digit" (e.g., 12)
The representation of the month. Possible values are:
  • "numeric" (e.g., 2)
  • "2-digit" (e.g., 02)
  • "long" (e.g., March)
  • "short" (e.g., Mar)
  • "narrow" (e.g., M). Two months may have the same narrow style for some locales (e.g. May's narrow style is also M).
The representation of the day. Possible values are:
  • "numeric" (e.g., 1)
  • "2-digit" (e.g., 01)
The representation of the hour. Possible values are "numeric", "2-digit".
The representation of the minute. Possible values are "numeric", "2-digit".
The representation of the second. Possible values are "numeric", "2-digit".
The representation of the time zone name. Possible values are:
  • "long" (e.g., British Summer Time)
  • "short" (e.g., GMT+1)

The default value for each date-time component property is undefined, but if all component properties are undefined, then year, month, and day are assumed to be "numeric".


Using DateTimeFormat

In basic use without specifying a locale, DateTimeFormat uses the default locale and default options.

var date = new Date(Date.UTC(2012, 11, 20, 3, 0, 0));

// toLocaleString without arguments depends on the implementation,
// the default locale, and the default time zone
console.log(new Intl.DateTimeFormat().format(date));
// → "12/19/2012" if run with en-US locale (language) and time zone America/Los_Angeles (UTC-0800)

Using timeStyle and dateStyle

let o = new Intl.DateTimeFormat("en" , {
  timeStyle: "short"
console.log(o.format(Date.now())); // "13:31 AM"

let o = new Intl.DateTimeFormat("en" , {
  dateStyle: "short"
console.log(o.format(Date.now())); // "07/07/20"

let o = new Intl.DateTimeFormat("en" , {
  timeStyle: "medium",
  dateStyle: "short"
console.log(o.format(Date.now())); // "07/07/20, 13:31:55 AM"


Browser compatibilityUpdate compatibility data on GitHub

Chrome Edge Firefox Internet Explorer Opera Safari
DateTimeFormat() constructor 24 12 29 11 15 10
dateStyle 76 No 79 No 63 No
hourCycle 73 18 58 No 60 13
IANA time zone names in timeZone option 24 14 52 No 15 10
timeStyle 76 No 79 No 63 No
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
DateTimeFormat() constructor 4.4 25 56 14 10 1.5
dateStyle 76 76 79 54 No No
hourCycle 73 73 58 52 13 No
IANA time zone names in timeZone option 37 25 56 14 10 1.5
timeStyle 76 76 79 54 No No
DateTimeFormat() constructor 13.0.0
Before version 13.0.0, only the locale data for en-US is available by default. When other locales are specified, the DateTimeFormat instance silently falls back to en-US. To make full ICU (locale) data available for versions prior to 13, see Node.js documentation on the --with-intl option and how to provide the data.
dateStyle 12.9.0
hourCycle 12.0.0
IANA time zone names in timeZone option 4.0.0
timeStyle 12.9.0

Implementation Progress

The following table provides a daily implementation status for new features that has not yet reached cross-browser stability. The data is generated by running the relevant feature tests in Test262, the standard test suite of JavaScript, in the nightly build, or latest release of each browser's JavaScript engine.

See also

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