# Is c8 ESM-only? Can you require() it?

> c8@12.0.0 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

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Last verified Sep 9, 2026 against c8@12.0.0.

c8 ships CommonJS only. require("c8") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^20.19.0 || ^22.12.0 || >=23. import "c8" 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("c8") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^20.19.0 || ^22.12.0 || >=23.
2. From ES modules use the default import: import c8 from "c8"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 12.0.0 (Jul 14, 2026)
- Module format: CommonJS
- Last CommonJS version: 12.0.0
- TypeScript types: bundled
- Node engines: ^20.19.0 || ^22.12.0 || >=23
- Weekly downloads: 3.7M
- License: ISC

## Runtime test results for c8@12.0.0

Installed and executed on Sep 9, 2026 with require("c8") from a CommonJS file and import "c8" from an ES module.

| Runtime | require("c8") | import "c8" |
|---|---|---|
| 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 c8

ES modules:

```js
import c8 from "c8";
```

CommonJS:

```js
const c8 = require("c8");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (68 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 3.2.0 – 12.0.0 | CommonJS | Sep 16, 2018 |

## Frequently asked

**Is c8 ESM-only?**

c8@12.0.0 is a CommonJS package. c8 ships CommonJS only. require("c8") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^20.19.0 || ^22.12.0 || >=23. import "c8" 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 c8 with ES module syntax?**

Yes. import c8 from "c8" 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 c8 work in Bun?**

Yes. import "c8" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does c8 ship TypeScript types?**

Yes. c8 bundles its own type declarations; no @types package is needed.

## Links

- [c8 on npm](https://www.npmjs.com/package/c8)
- [Source repository](https://github.com/bcoe/c8)
- [HTML version](https://canirequire.com/package/c8/)
- [JSON version](https://canirequire.com/package/c8.json)

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