Intl.PluralRules() constructor

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 parameter description on the Intl main page.

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.

type

The type to use. Possible values are:

• "cardinal" for cardinal numbers (referring to the quantity of things). This is the default value.
• "ordinal" for ordinal number (referring to the ordering or ranking of things, e.g. "1st", "2nd", "3rd" in English).

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 21.

In basic use without specifying a locale, a formatted string in the default locale and with default options is returned. This is useful to distinguish between singular and plural forms, e.g. "dog" and "dogs".

const pr = new Intl.PluralRules();

pr.select(0); // 'other' if in US English locale

pr.select(1); // 'one' if in US English locale

pr.select(2); // 'other' if in US English locale

The results can be customized using the options argument, which has one property called type which you can set to ordinal. This is useful to figure out the ordinal indicator, e.g. "1st", "2nd", "3rd", "4th", "42nd" and so forth.

const pr = new Intl.PluralRules("en-US", { type: "ordinal" });

const suffixes = new Map([
  ["one", "st"],
  ["two", "nd"],
  ["few", "rd"],
  ["other", "th"],
]);
const formatOrdinals = (n) => {
  const rule = pr.select(n);
  const suffix = suffixes.get(rule);
  return `${n}${suffix}`;
};

formatOrdinals(0); // '0th'
formatOrdinals(1); // '1st'
formatOrdinals(2); // '2nd'
formatOrdinals(3); // '3rd'
formatOrdinals(4); // '4th'
formatOrdinals(11); // '11th'
formatOrdinals(21); // '21st'
formatOrdinals(42); // '42nd'
formatOrdinals(103); // '103rd'

• Intl.PluralRules
• Intl