Intl.getCanonicalLocales()

The Intl.getCanonicalLocales() static method returns an array containing the canonical locale names. Duplicates will be omitted and elements will be validated as structurally valid language tags.

{{InteractiveExample("JavaScript Demo: Intl.getCanonicalLocales()")}}

```js interactive-example console.log(Intl.getCanonicalLocales("EN-US")); // Expected output: Array ["en-US"]

console.log(Intl.getCanonicalLocales(["EN-US", "Fr"])); // Expected output: Array ["en-US", "fr"]

try { Intl.getCanonicalLocales("EN_US"); } catch (err) { console.log(err.toString()); // Expected output: RangeError: invalid language tag: "EN_US" }

## Syntax

```js-nolint
Intl.getCanonicalLocales(locales)

Parameters#

• locales
• : A list of {{jsxref("String")}} values for which to get the canonical locale names.

Return value#

An array containing the canonical locale names.

Examples#

Using getCanonicalLocales#

Intl.getCanonicalLocales("EN-US"); // ["en-US"]
Intl.getCanonicalLocales(["EN-US", "Fr"]); // ["en-US", "fr"]

Intl.getCanonicalLocales("EN_US");
// RangeError: invalid language tag: "EN_US"

Specifications#

{{Specifications}}

Browser compatibility#

{{Compat}}

See also#

• Polyfill of Intl.getCanonicalLocales in FormatJS
• {{jsxref("Intl/NumberFormat/supportedLocalesOf", "Intl.NumberFormat.supportedLocalesOf()")}}
• {{jsxref("Intl/DateTimeFormat/supportedLocalesOf", "Intl.DateTimeFormat.supportedLocalesOf()")}}
• {{jsxref("Intl/Collator/supportedLocalesOf", "Intl.Collator.supportedLocalesOf()")}}