# Is mdn-data ESM-only? Can you require() it?

> mdn-data@2.35.0 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

Open Web data by the Mozilla Developer Network

Last verified Sep 9, 2026 against mdn-data@2.35.0.

mdn-data ships CommonJS only. require("mdn-data") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "mdn-data" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.

## What to do

1. require("mdn-data") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun.
2. From ES modules use the default import: import mdnData from "mdn-data"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: no types are available for mdn-data; declare the module yourself if you need them.

## Facts

- Latest: 2.35.0 (Sep 2, 2026)
- Module format: CommonJS
- Last CommonJS version: 2.35.0
- TypeScript types: none
- Node engines: not declared
- Weekly downloads: 105.3M
- License: CC0-1.0

## Runtime test results for mdn-data@2.35.0

Installed and executed on Sep 9, 2026 with require("mdn-data") from a CommonJS file and import "mdn-data" from an ES module.

| Runtime | require("mdn-data") | import "mdn-data" |
|---|---|---|
| Node.js 18 | works | works |
| Node.js 20 | works | works |
| Node.js 22 | works | works |
| Node.js 24 | works | works |
| Node.js 26 | works | works |
| Bun 1.4.0 | works | works |

## How to import mdn-data

ES modules:

```js
import mdnData from "mdn-data";
```

CommonJS:

```js
const mdnData = require("mdn-data");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (91 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 2.0.24 – 2.35.0 | CommonJS | Dec 15, 2021 |

## Frequently asked

**Is mdn-data ESM-only?**

mdn-data@2.35.0 is a CommonJS package. mdn-data ships CommonJS only. require("mdn-data") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "mdn-data" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.

**Can I import mdn-data with ES module syntax?**

Yes. import mdnData from "mdn-data" works in Node.js and Bun because they support importing CommonJS modules. Named imports work only when Node.js can statically detect the exports.

**Does mdn-data work in Bun?**

Yes. import "mdn-data" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does mdn-data ship TypeScript types?**

No. mdn-data ships no type declarations and there is no @types package for it.

## Links

- [mdn-data on npm](https://www.npmjs.com/package/mdn-data)
- [Source repository](https://github.com/mdn/data)
- [HTML version](https://canirequire.com/package/mdn-data/)
- [JSON version](https://canirequire.com/package/mdn-data.json)

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