# Is buffer-crc32 ESM-only? Can you require() it?

> buffer-crc32@1.0.0 ships CommonJS and ESM builds. Dual package — require() works on every Node.js version we test; import works too.

A pure javascript CRC32 algorithm that plays nice with binary data

Last verified Sep 9, 2026 against buffer-crc32@1.0.0.

buffer-crc32 publishes both a CommonJS entry and a native ESM entry (ESM added in 1.0.0). require("buffer-crc32") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=8.0.0. import "buffer-crc32" works alongside it.

## What to do

1. Nothing to change. require("buffer-crc32") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=8.0.0. import * as bufferCrc32 from "buffer-crc32" works alongside it; use named imports for what the ESM entry exports.
2. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 1.0.0 (Feb 6, 2024)
- Module format: Dual (CommonJS + ESM)
- Last CommonJS version: 1.0.0
- Native ESM since: 1.0.0
- TypeScript types: bundled
- Node engines: >=8.0.0
- Weekly downloads: 64.5M
- License: MIT

## Runtime test results for buffer-crc32@1.0.0

Installed and executed on Sep 9, 2026 with require("buffer-crc32") from a CommonJS file and import "buffer-crc32" from an ES module.

| Runtime | require("buffer-crc32") | import "buffer-crc32" |
|---|---|---|
| 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 buffer-crc32

ES modules:

```js
import * as bufferCrc32 from "buffer-crc32";
```

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

CommonJS:

```js
const bufferCrc32 = require("buffer-crc32");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (16 versions; the newest 16 shown).

| Versions | Format | First published |
|---|---|---|
| 1.0.0 | Dual (CommonJS + ESM) | Feb 6, 2024 |
| 0.1.0 – 0.2.13 | CommonJS | Jul 11, 2012 |

## Frequently asked

**Is buffer-crc32 ESM-only?**

buffer-crc32@1.0.0 ships CommonJS and ESM builds. buffer-crc32 publishes both a CommonJS entry and a native ESM entry (ESM added in 1.0.0). require("buffer-crc32") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=8.0.0. import "buffer-crc32" works alongside it.

**Can I require buffer-crc32?**

Yes. buffer-crc32 ships a CommonJS entry alongside the native ESM entry. require("buffer-crc32") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=8.0.0.

**Does buffer-crc32 work in Bun?**

Yes. import "buffer-crc32" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does buffer-crc32 ship TypeScript types?**

Yes. buffer-crc32 bundles its own type declarations; no @types package is needed.

## Links

- [buffer-crc32 on npm](https://www.npmjs.com/package/buffer-crc32)
- [Source repository](https://github.com/brianloveswords/buffer-crc32)
- [HTML version](https://canirequire.com/package/buffer-crc32/)
- [JSON version](https://canirequire.com/package/buffer-crc32.json)

---

For scripts and AI agents: any package is at https://canirequire.com/package/<name>/index.md (Markdown) or https://canirequire.com/package/<name>.json (JSON); the site index is https://canirequire.com/llms.txt. Fetch the URL directly; no search needed.