Intl.Locale.prototype.timeZones

Returns an array with supported time zones for the associated Locale, where each value is an IANA time zone canonical name, sorted in alphabetical order. If the locale identifier does not contain a region subtag, the returned value is undefined.

List supported time zones for a given Locale.

const arEG = new Intl.Locale("ar-EG");
console.log(arEG.timeZones); // ["Africa/Cairo"]

const jaJP = new Intl.Locale("ja-JP");
console.log(jaJP.timeZones); // ["Asia/Tokyo"]

const ar = new Intl.Locale("ar");
console.log(ar.timeZones); // undefined

• Intl.Locale
• IANA time zone database