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

> cssom@0.5.0 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

CSS Object Model implementation and CSS parser

Last verified Sep 9, 2026 against cssom@0.5.0.

cssom ships CommonJS only. require("cssom") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "cssom" 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("cssom") 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 cssom from "cssom"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: npm install -D @types/cssom

## Facts

- Latest: 0.5.0 (Jun 20, 2021)
- Module format: CommonJS
- Last CommonJS version: 0.5.0
- TypeScript types: @types/cssom
- Node engines: not declared
- Weekly downloads: 41.7M
- License: MIT

## Runtime test results for cssom@0.5.0

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

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

ES modules:

```js
import cssom from "cssom";
```

CommonJS:

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

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (21 versions; the newest 21 shown).

| Versions | Format | First published |
|---|---|---|
| 0.2.0 – 0.5.0 | CommonJS | Oct 24, 2011 |

## Frequently asked

**Is cssom ESM-only?**

cssom@0.5.0 is a CommonJS package. cssom ships CommonJS only. require("cssom") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "cssom" 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 cssom with ES module syntax?**

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

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

**Does cssom ship TypeScript types?**

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

## Links

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

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