Setting Up Gzip Compression for Better Web Performance Compression is a simple, effective way to save bandwidth and speed up your site. I hesitated when recommending gzip compression for speeding up your JavaScript due to problems in older browsers. But it's the 21st century. Most of my traffic comes from modern browsers, and quite frankly, most of my users are fairly tech-savvy. I don't want to slow everyone else down because somebody is chugging along on IE 4.0 on Windows 95. Google and Yahoo use gzip compression. A modern browser is needed to enjoy modern web content and modern web speed — so gzip encoding it is. Here's how to set it up. Wait, wait, wait: Why are we doing this? Before we start, I should explain what content encoding is. When you request a file like http://www.yahoo.com/index.html , your browser talks to a web server. The conversation goes a little like this: