So your site is running a bit slow but you have followed the golden rules or site optimization, how do you find where the bottlenecks are and how to fix them. These tools should help you identify performance issues with your site and even how to fix them.
WebPageTest – This is currently my favorite testing tool, it is an online tool where you input your URL and then the test page refreshes with the performance test results. The results include both the ‘waterfall’ graphic of load times for the page components and a grading of the adherence to best practices. There isn’t the same information overload as with Google PageSpeed and it offers the ability to test the load speed from five different geographic locations (which can help test if your CDN is working for you) .
WebPageTest crucially allows loads to be tested on different browsers, this is a great addition as browsers vary in their ability to load page resources simultaneously which can have a dramatic impact on the page load time.
Pingdom Load Test – Pingdom offers a very robust website monitoring service but it also offers a free page load test tool. This is a very simple tool which can be quickly run to determine the speed of the components in a page load. This tool runs a little faster than the WebPageTest tool but has few of its features.