Intl.Locale.prototype.numeric

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 numeric accessor property of Intl.Locale instances returns whether this locale has special collation handling for numeric characters.

Description

Like caseFirst, numeric represents a modification to the collation rules utilized by the locale. numeric is a boolean value, which means that it can be either true or false. If numeric is set to false, there will be no special handling of numeric values in strings. If numeric is set to true, then the locale will take numeric characters into account when collating strings. This special numeric handling means that sequences of decimal digits will be compared as numbers. For example, the string "A-21" will be considered less than "A-123".

The numeric property's value is set at construction time, either through the kn key of the locale identifier or through the numeric option of the Intl.Locale() constructor. The latter takes priority if they are both present; and if neither is present, the property has value undefined.

The set accessor of numeric is undefined. You cannot change this property directly.

Examples

Like other locale subtags, the numeric value can be added to the Intl.Locale object via the locale string, or a configuration object argument to the constructor.

Adding a numeric value via the locale string

In the Unicode locale string spec, numeric is an "extension subtag". These subtags add additional data about the locale, and are added to locale identifiers using the -u extension key. To add the numeric value to the initial locale identifier string passed into the Intl.Locale() constructor, first add the -u extension key if it doesn't exist. Next, add the -kn extension to indicate that you are adding a value for numeric. Finally, add the numeric value. If you want to set numeric to true, adding the kn key will suffice. To set the value to false, you must specify in by adding "false" after the kn key.

js
const locale = new Intl.Locale("fr-Latn-FR-u-kn-false");
console.log(locale.numeric); // "false"

Adding a numeric value via the configuration object argument

The Intl.Locale() constructor has an optional configuration object argument, which can contain any of several extension types, including numeric. Set the numeric property of the configuration object to your desired numeric value, and then pass it into the constructor.

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

Specifications

Specification
ECMAScript® 2026 Internationalization API Specification
# sec-Intl.Locale.prototype.numeric

Browser compatibility

See also