is-language-code

Is given string a language code (as per IANA)

Install

This package is pure ESM. If you're not ready yet, install an older version of this program, 3.1.0 (npm i is-language-code@3.1.0).

npm i is-language-code

Quick Take

import { strict as assert } from "assert";

import { isLangCode } from "is-language-code";

assert.deepEqual(isLangCode("de-419-DE"), {
  res: false,
  message: 'Two region subtags, "419" and "de".',
});

assert.deepEqual(isLangCode("sr-Latn"), {
  res: true,
  message: null,
});

Documentation

Please visit codsen.com for a full description of the API. Also, try the GUI playground.

Contributing

To report bugs or request features or assistance, raise an issue on GitHub.

Licence

MIT License.

Copyright © 2010-2025 Roy Revelt and other contributors.