---
title: zlib
description: Use the Node.js zlib module in Workers for Gzip, Deflate, and Brotli compression.
image: https://developers.cloudflare.com/dev-products-preview.png
---

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# zlib

Note

To enable built-in Node.js APIs and polyfills, add the nodejs\_compat compatibility flag to your [Wrangler configuration file](https://developers.cloudflare.com/workers/wrangler/configuration/). This also enables nodejs\_compat\_v2 as long as your compatibility date is 2024-09-23 or later. [Learn more about the Node.js compatibility flag and v2](https://developers.cloudflare.com/workers/configuration/compatibility-flags/#nodejs-compatibility-flag).

The node:zlib module provides compression functionality implemented using Gzip, Deflate/Inflate, and Brotli. To access it:

JavaScript

```
import zlib from "node:zlib";
```

The full `node:zlib` API is documented in the [Node.js documentation for node:zlib ↗](https://nodejs.org/api/zlib.html).

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```