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

> clean-css@5.3.3 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

A well-tested CSS minifier

Last verified Sep 9, 2026 against clean-css@5.3.3.

clean-css ships CommonJS only. require("clean-css") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 10.0. import "clean-css" 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("clean-css") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 10.0.
2. From ES modules use the default import: import cleanCss from "clean-css"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: npm install -D @types/clean-css

## Facts

- Latest: 5.3.3 (Nov 30, 2023)
- Module format: CommonJS
- Last CommonJS version: 5.3.3
- TypeScript types: @types/clean-css
- Node engines: >= 10.0
- Weekly downloads: 19.2M
- License: MIT

## Runtime test results for clean-css@5.3.3

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

| Runtime | require("clean-css") | import "clean-css" |
|---|---|---|
| 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 clean-css

ES modules:

```js
import cleanCss from "clean-css";
```

CommonJS:

```js
const cleanCss = require("clean-css");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (211 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 3.4.17 – 5.3.3 | CommonJS | Jun 4, 2016 |

## Frequently asked

**Is clean-css ESM-only?**

clean-css@5.3.3 is a CommonJS package. clean-css ships CommonJS only. require("clean-css") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 10.0. import "clean-css" 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 clean-css with ES module syntax?**

Yes. import cleanCss from "clean-css" 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 clean-css work in Bun?**

Yes. import "clean-css" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does clean-css ship TypeScript types?**

Not bundled. Install the community types with "npm install -D @types/clean-css".

## Links

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

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