Speed is a crucial aspect in providing a pleasant user experience to visitors of your site. It ensures that a visitor's limited attention span and time are spent on actual content and not wasted waiting for images and scripts to load. Studies have shown that users will not tolerate more than a 4 second load time. If your site fails to offer a quick response, your users will leave.

In terms of SEO, Google is hinting at using Page Speed score in its ranking algorithm. As developers and marketers look to optimize their sites, page speed should be among the top optimizations to consider.

Two of the major speed analysis tools are Google's Page Speed and Yahoo's YSlow. Both require Firefox and the Firebug add-on.

Here's a run down of each:

Page Speed

"When you profile a web page with Page Speed, it evaluates the page's conformance to a number of different rules. These rules are general front-end best practices you can apply at any stage of web development. We provide documentation of each of the rules here, so whether or not you run the Page Speed tool - maybe you're just developing a brand new site and aren't ready to test it, you can refer to these pages at any time. We give you specific tips and suggestions for how you can best implement the rules and incorporate them into your development process."

Read more about Google Page Speed


"YSlow grades web page based on one of three predefined ruleset or a user-defined ruleset. It offers suggestions for improving the page's performance, summarizes the page's components, displays statistics about the page, and provides tools for performance analysis, including™ and JSLint."

Read more about Yahoo! YSlow

What's the difference?

Page Speed and YSlow generally offer the same service, however there are differences in their calculations. Each service analyzes a page using a set of rules that they believe are most relevant to page speed and performance. Most of the rules overlap or are very similar to each other, but in general your scores should be comparable.

The benefit of GTmetrix is that you can analyze your page using both services, giving you different perspectives on how to optimize your code.

On the side you'll find a complete list of best practices as defined by each service.

WordPress Optimization Guide

A lot of our users run WordPress as a platform for their site. As a result, we've come up with an optimization guide to ensure that even the most basic WordPress installs are running optimally.

Read our WordPress Optimization Guide »

Magento Optimization Guide

Magento is a very popular eCommerce platform and many of our users have been requesting optimization tips; thus, GTspeed was born! We developed a speed optimization plugin for Magento to optimize Magento installs quickly and easily!

Read our Magento Optimization Guide »

Why is My Page Slow?

The speed of a page is made up of both Front-end and Server-side components. While your front-end structure may be speedy, the generation of your page (the server-side) also plays an important role in page load times. Read more about how it works and explore possible solutions for a slow server-side.

Find out why your page is slow »

Why use a CDN?

Content Distribution Networks (CDNs) cache resources in servers located throughout the world. This allows users who request a site originating from another region to still experience a relatively fast page load, due to being geographically closer to an edge server. Read more about CDNs in detail and find out whether or not they're right for you.

Find out why you should use a CDN »