is-language-code/README.md

Is given string a language code (as per IANA)

<h1 align="center">is-language-code</h1>

<p align="center">Is given string a language code (as per IANA)</p>

<p align="center">
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</p>

## Install

This package is [pure ESM](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c). If you're not ready yet, install an older version of this program, 3.1.0 (`npm i is-language-code@3.1.0`).

```bash
npm i is-language-code
```

## Quick Take

```js
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](https://codsen.com/os/is-language-code/) for a full description of the API. Also, try the [GUI playground](https://codsen.com/os/is-language-code/play).

## Contributing

To report bugs or request features or assistance, [raise an issue](https://github.com/codsen/codsen/issues/new/choose) on GitHub.

## Licence

MIT License.

Copyright © 2010-2025 Roy Revelt and other contributors.

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