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

> autoprefixer@10.5.5 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

Parse CSS and add vendor prefixes to CSS rules using values from the Can I Use website

Last verified Sep 9, 2026 against autoprefixer@10.5.5.

autoprefixer ships CommonJS only. require("autoprefixer") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^10 || ^12 || >=14. import "autoprefixer" 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("autoprefixer") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^10 || ^12 || >=14.
2. From ES modules use the default import: import autoprefixer from "autoprefixer"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 10.5.5 (Sep 4, 2026)
- Module format: CommonJS
- Last CommonJS version: 10.5.5
- TypeScript types: bundled
- Node engines: ^10 || ^12 || >=14
- Weekly downloads: 56.7M
- License: MIT

## Runtime test results for autoprefixer@10.5.5

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

| Runtime | require("autoprefixer") | import "autoprefixer" |
|---|---|---|
| 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 autoprefixer

ES modules:

```js
import autoprefixer from "autoprefixer";
```

CommonJS:

```js
const autoprefixer = require("autoprefixer");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (257 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 9.8.4 – 10.5.5 | CommonJS | Jun 24, 2020 |

## Frequently asked

**Is autoprefixer ESM-only?**

autoprefixer@10.5.5 is a CommonJS package. autoprefixer ships CommonJS only. require("autoprefixer") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^10 || ^12 || >=14. import "autoprefixer" 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 autoprefixer with ES module syntax?**

Yes. import autoprefixer from "autoprefixer" 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 autoprefixer work in Bun?**

Yes. import "autoprefixer" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does autoprefixer ship TypeScript types?**

Yes. autoprefixer bundles its own type declarations; no @types package is needed.

## Links

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

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