Best free tools to measure real loading times

The tools described in this section will perform more than one task. They will measure various aspects of performance and provide tools and means of implementing the solutions they offer. First and fore most it is important you measure the real end user experience. There are many commercial tools to help you out, but the ones here are all for free.

• Webpagetest.org
  Based on the desktop app AOL Pagetest and available either as a self hosted PHP app or as as web based app, this tool has one unique feature; it analyzes how your web pages load on Internet Explorer 6 to 9 and Google Chrome 11 from a variety of locations in the world; US, China, UK, France, New Zealand, Russia, India and many more.
  It also differs from others tools in the following important ways:
  1. It will give you a PageSpeed score and a Yslow rating side by side.
  2. It will visually show you, in a waterfall kind of graph, each of the resources being loaded on your site in the order in which they are loaded, their size and the time taken to load each.
  3. It will generate a nice checklist of optimization tasks you can perform to make your site faster.
  4. It will breakdown the content by the number of requests made and the size of all requests for each type of content, and show them in a nice pie chart. This means that at a glance, you can know which resource is hogging your page down.
  5. It will summarise all of the above and show you how fast your site loads the first time and the second time.

  By the sheer comprehensiveness of this tool, it wins our Editors Choice award.

The following tools do provide some end2end insights, but don’t have the real monitoring that webpagetest.org provides. Though very helpful for further insights.

• FireBug
  Firebug provides a number of co-related features such as DOM inspection, JavaScript and CSS code debugging, monitoring and analysis of a website’s network traffic and a JavaScript profiler, among other features. This is one tool you don’t want to be without.
• YSlow
  An extension to Firebug, this tool adds important performance optimization functionality by analyzing pages and grading them according to pre-defined rulesets or even a use defined set of rules. It then provides tools to actualize the suggested performance tweaks (see Smush.it and JSLint below). The predefined rulesets are based on Yahoo’s best practices for speeding up websites.
• PageSpeed
  Available as an addon, a hosted service and also as an Apache module, this tool make it easier to rate your website against and implement Google’s web performance best practices.
• Web Developer Toolbar
  This nifty addon available for Firefox and Chrome provides a rich set of tools for working with cookies, CSS, images, forms, Javascript and HTML. This tool is a must-have.
• W3C Log Validator
  This tool combines the W3C Markup Validator, The W3C Link Checker and the W3C CSS Validator to give a more wholesome analysis and measurement of your website. By using the web server’s access logs, it works on the most popular files, thereby allowing the developer to work on the most important pages first.
• W3C Unified Validator
  Works almost similar to the Log Validator, only that it is web based whilst Log Validator is an installed software. It checks for validity of HTML, CSS and RSS feeds.