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

> markdown-it-anchor@10.0.0 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

Header anchors for markdown-it.

Last verified Sep 9, 2026 against markdown-it-anchor@10.0.0.

markdown-it-anchor ships CommonJS only. require("markdown-it-anchor") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "markdown-it-anchor" 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.

It also declares a "module" field, so bundlers such as webpack, Vite and esbuild pick up an ESM build for tree-shaking.

## What to do

1. require("markdown-it-anchor") 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 markdownItAnchor from "markdown-it-anchor"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 10.0.0 (Sep 5, 2026)
- Module format: CommonJS
- Last CommonJS version: 10.0.0
- TypeScript types: bundled
- Node engines: not declared
- Weekly downloads: 3.6M
- License: Unlicense

## Runtime test results for markdown-it-anchor@10.0.0

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

| Runtime | require("markdown-it-anchor") | import "markdown-it-anchor" |
|---|---|---|
| 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 markdown-it-anchor

ES modules:

```js
import markdownItAnchor from "markdown-it-anchor";
```

CommonJS:

```js
const markdownItAnchor = require("markdown-it-anchor");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (69 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 2.3.1 – 10.0.0 | CommonJS | Nov 29, 2015 |

## Frequently asked

**Is markdown-it-anchor ESM-only?**

markdown-it-anchor@10.0.0 is a CommonJS package. markdown-it-anchor ships CommonJS only. require("markdown-it-anchor") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "markdown-it-anchor" 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 markdown-it-anchor with ES module syntax?**

Yes. import markdownItAnchor from "markdown-it-anchor" 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 markdown-it-anchor work in Bun?**

Yes. import "markdown-it-anchor" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does markdown-it-anchor ship TypeScript types?**

Yes. markdown-it-anchor bundles its own type declarations; no @types package is needed.

## Links

- [markdown-it-anchor on npm](https://www.npmjs.com/package/markdown-it-anchor)
- [Source repository](https://github.com/valeriangalliat/markdown-it-anchor)
- [HTML version](https://canirequire.com/package/markdown-it-anchor/)
- [JSON version](https://canirequire.com/package/markdown-it-anchor.json)

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