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

> pako@3.0.1 ships CommonJS and ESM builds. Dual package — require() works on every Node.js version we test; import works too.

zlib port to javascript - fast, modularized, with browser support

Last verified Sep 9, 2026 against pako@3.0.1.

pako publishes both a CommonJS entry and a native ESM entry (ESM added in 2.0.0). require("pako") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "pako" works alongside it.

## What to do

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

## Facts

- Latest: 3.0.1 (Jul 6, 2026)
- Module format: Dual (CommonJS + ESM)
- Last CommonJS version: 3.0.1
- Native ESM since: 2.0.0
- TypeScript types: bundled
- Node engines: not declared
- Weekly downloads: 100.8M
- License: (MIT AND Zlib)

## Runtime test results for pako@3.0.1

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

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

ES modules:

```js
import * as pako from "pako";
```

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

CommonJS:

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

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (34 versions; the newest 34 shown).

| Versions | Format | First published |
|---|---|---|
| 2.0.0 – 3.0.1 | Dual (CommonJS + ESM) | Nov 17, 2020 |
| 0.0.0 – 1.0.11 | CommonJS | Feb 19, 2014 |

## Frequently asked

**Is pako ESM-only?**

pako@3.0.1 ships CommonJS and ESM builds. pako publishes both a CommonJS entry and a native ESM entry (ESM added in 2.0.0). require("pako") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "pako" works alongside it.

**Can I require pako?**

Yes. pako ships a CommonJS entry alongside the native ESM entry. require("pako") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun.

**Does pako work in Bun?**

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

**Does pako ship TypeScript types?**

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

## Links

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