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

> ansi-regex@6.3.0 is ESM-only. ESM-only since 6.0.0 — last CommonJS version is 5.0.1.

Regular expression for matching ANSI escape codes

Last verified Sep 9, 2026 against ansi-regex@6.3.0.

ansi-regex dropped its CommonJS build in 6.0.0 (April 2021). The last version with a plain require()-able CommonJS entry is 5.0.1, published Sep 14, 2021; it declares support for Node.js >=8.

On Node.js 20.19+, 22.12+ and newer, require("ansi-regex") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26. On Node.js 18, which has no require(esm), require("ansi-regex") fails with ERR_REQUIRE_ESM.

## What to do

1. On Node.js 20.19+, 22.12+ and newer, require("ansi-regex") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26.
2. From a CommonJS file, use a dynamic import inside an async function: const ansiRegex = await import("ansi-regex"). That works on every Node.js version the package supports (>=12).
3. If you need a synchronous require() or run Node.js 18: npm install ansi-regex@5.0.1, the last CommonJS release (published Sep 14, 2021); it declares Node.js >=8.
4. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 6.3.0 (Aug 12, 2026)
- Module format: ESM-only
- Last CommonJS version: 5.0.1
- ESM-only since: 6.0.0 (Apr 16, 2021)
- TypeScript types: bundled
- Node engines: >=12
- Weekly downloads: 345.3M
- License: MIT

## Runtime test results for ansi-regex@6.3.0

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

| Runtime | require("ansi-regex") | import "ansi-regex" |
|---|---|---|
| Node.js 18 | fails (ERR_REQUIRE_ESM) | 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 ansi-regex

ES modules:

```js
import * as ansiRegex from "ansi-regex";
```

Namespace import shown because the ESM entry may have no default export; use named imports for what it exports.

CommonJS:

```js
// Node.js 20.19+, 22.12+ and newer (verified):
const ansiRegex = require("ansi-regex");

// Any Node.js version the package supports (>=12), from an async function:
async function main() {
  const ansiRegex = await import("ansi-regex");
}

// Or pin the last CommonJS release (declares Node.js >=8):
// npm install ansi-regex@5.0.1
```

## 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 |
|---|---|---|
| 6.0.0 – 6.3.0 | ESM-only | Apr 16, 2021 |
| 0.1.0 – 5.0.1 | CommonJS | Jun 3, 2014 |

## Frequently asked

**Is ansi-regex ESM-only?**

ansi-regex@6.3.0 is ESM-only. ansi-regex dropped its CommonJS build in 6.0.0 (April 2021). The last version with a plain require()-able CommonJS entry is 5.0.1, published Sep 14, 2021; it declares support for Node.js >=8.

**Which version of ansi-regex still supports CommonJS / require()?**

5.0.1 is the last version of ansi-regex with a CommonJS build; it declares Node.js >=8. Install it with "npm install ansi-regex@5.0.1". Every version from 6.0.0 on is ESM-only.

**How do I use ansi-regex from a CommonJS file?**

From a CommonJS file, use a dynamic import inside an async function: const ansiRegex = await import("ansi-regex"). That works on every Node.js version the package supports (>=12). On Node.js 20.19+, 22.12+ and newer, require("ansi-regex") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26. Alternatively pin ansi-regex@5.0.1 (declares Node.js >=8).

**Does ansi-regex work in Bun?**

Yes. import "ansi-regex" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does ansi-regex ship TypeScript types?**

Yes. ansi-regex bundles its own type declarations; no @types package is needed.

## Links

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

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