# Is w3c-xmlserializer ESM-only? Can you require() it?

> w3c-xmlserializer@5.0.0 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

A per-spec XML serializer implementation

Last verified Sep 9, 2026 against w3c-xmlserializer@5.0.0.

w3c-xmlserializer ships CommonJS only. require("w3c-xmlserializer") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=18. import "w3c-xmlserializer" 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("w3c-xmlserializer") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=18.
2. From ES modules use the default import: import w3cXmlserializer from "w3c-xmlserializer"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: npm install -D @types/w3c-xmlserializer

## Facts

- Latest: 5.0.0 (Nov 12, 2023)
- Module format: CommonJS
- Last CommonJS version: 5.0.0
- TypeScript types: @types/w3c-xmlserializer
- Node engines: >=18
- Weekly downloads: 76.4M
- License: MIT

## Runtime test results for w3c-xmlserializer@5.0.0

Installed and executed on Sep 9, 2026 with require("w3c-xmlserializer") from a CommonJS file and import "w3c-xmlserializer" from an ES module.

| Runtime | require("w3c-xmlserializer") | import "w3c-xmlserializer" |
|---|---|---|
| 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 w3c-xmlserializer

ES modules:

```js
import w3cXmlserializer from "w3c-xmlserializer";
```

CommonJS:

```js
const w3cXmlserializer = require("w3c-xmlserializer");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (12 versions; the newest 12 shown).

| Versions | Format | First published |
|---|---|---|
| 0.0.1 – 5.0.0 | CommonJS | Jul 1, 2018 |

## Frequently asked

**Is w3c-xmlserializer ESM-only?**

w3c-xmlserializer@5.0.0 is a CommonJS package. w3c-xmlserializer ships CommonJS only. require("w3c-xmlserializer") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=18. import "w3c-xmlserializer" 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 w3c-xmlserializer with ES module syntax?**

Yes. import w3cXmlserializer from "w3c-xmlserializer" 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 w3c-xmlserializer work in Bun?**

Yes. import "w3c-xmlserializer" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does w3c-xmlserializer ship TypeScript types?**

Not bundled. Install the community types with "npm install -D @types/w3c-xmlserializer".

## Links

- [w3c-xmlserializer on npm](https://www.npmjs.com/package/w3c-xmlserializer)
- [Source repository](https://github.com/jsdom/w3c-xmlserializer)
- [HTML version](https://canirequire.com/package/w3c-xmlserializer/)
- [JSON version](https://canirequire.com/package/w3c-xmlserializer.json)

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