Requirements
Runtime Configuration
Installing/Configuring
PHP Manual

## Installation

Zlib support in PHP is not enabled by default. You will need to configure PHP --with-zlib[=DIR]

The Windows version of PHP has built-in support for this extension. You do not need to load any additional extensions in order to use these functions.

> Note: Built-in support for zlib on Windows is available with PHP 4.3.0.