# is-language-code

> Is given string a language code (as per IANA)

Latest version **5.2.2** (published 2026-09-06) · MIT license · 0 weekly downloads

## Install

```sh
npm install is-language-code
pnpm add is-language-code
yarn add is-language-code
bun add is-language-code
```

## Health

**Score 75/100 (B)** — status: active.

Positive: has types; esm support; no vulnerabilities; has provenance; recently updated; high maintenance score; high quality score.

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 5.2.2 |
| Published | 2026-09-06 |
| First published | 2020-01-05 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM |
| Node | >=18.20.8 |
| Dependencies | 0 |
| Unpacked size | 133.8 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 213 |
| Author | Roy Revelt |
| Maintainers | royston |
| Keywords | check, code, codes, iana, ietf, is, langref, language, lookup, registry, rfc, rfc 5646, seo, standards, valid, validate |

## Links

- npm: https://www.npmjs.com/package/is-language-code
- Repository: https://github.com/codsen/codsen
- Homepage: https://codsen.com/os/is-language-code
- Issues: https://github.com/codsen/codsen/issues
- npm.io page: https://npm.io/package/is-language-code

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## Recent versions

- 5.2.2 (latest) — 2026-09-06
- 5.2.1 — 2026-09-01
- 5.2.0 — 2026-08-19
- 5.1.3 — 2026-01-15
- 5.1.0 — 2025-10-15
- 5.0.27 — 2025-10-12
- 5.0.26 — 2025-10-08
- 5.0.25 — 2025-10-07
- 5.0.16 — 2025-07-21
- 5.0.15 — 2025-03-02
- 5.0.12 — 2024-01-31
- 5.0.11 — 2024-01-05
- 5.0.10 — 2023-12-20
- 5.0.9 — 2023-09-11
- 5.0.8 — 2023-07-14
- … 76 more at https://npm.io/package/is-language-code/versions

## README

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

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

<p align="center">
  <a href="https://codsen.com/os/is-language-code" rel="nofollow noreferrer noopener">
    <img src="https://img.shields.io/badge/-codsen-blue?style=flat-square" alt="page on codsen.com">
  </a>
  <a href="https://www.npmjs.com/package/is-language-code" rel="nofollow noreferrer noopener">
    <img src="https://img.shields.io/badge/-npm-blue?style=flat-square" alt="page on npm">
  </a>
  <a href="https://github.com/codsen/codsen/tree/main/packages/is-language-code" rel="nofollow noreferrer noopener">
    <img src="https://img.shields.io/badge/-github-blue?style=flat-square" alt="page on github">
  </a>
  <a href="https://npmcharts.com/compare/is-language-code?interval=30" rel="nofollow noreferrer noopener" target="_blank">
    <img src="https://img.shields.io/npm/dm/is-language-code.svg?style=flat-square" alt="Downloads per month">
  </a>
  <a href="https://codsen.com/os/is-language-code/changelog" rel="nofollow noreferrer noopener">
    <img src="https://img.shields.io/badge/changelog-here-brightgreen?style=flat-square" alt="changelog">
  </a>
  <img src="https://img.shields.io/badge/licence-MIT-brightgreen.svg?style=flat-square" alt="MIT Licence">
  <a href="https://codsen.com/os/is-language-code/play"><img src="https://img.shields.io/badge/playground-here-brightgreen?style=flat-square" alt="playground"></a>
</p>

**No dependencies whatsoever.** This package declares no dependencies or devDependencies.

## 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 "node:assert";

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

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. For **Changelog**, see [raw md on GitHub](https://github.com/codsen/codsen/blob/main/packages/is-language-code/CHANGELOG.md) or [the website](https://codsen.com/os/is-language-code/changelog). 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 © 2010-2026 Roy Revelt and other contributors

<p align="center"><img src="https://codsen.com/images/png-codsen-ok.png" width="98" alt="ok" align="center"> <img src="https://codsen.com/images/png-codsen-1.png" width="148" alt="codsen" align="center"> <img src="https://codsen.com/images/png-codsen-star-small.png" width="32" alt="star" align="center"></p>

---
_Source: https://npm.io/package/is-language-code · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._