You can dig deep into your results down to the root to find out what are the issues that are leading to your website being slow. There are a lot of options which you can select to narrow down your results namely timelines, content breakdowns, processing breakdowns and incredibly detailed performance reviews.
If you'd like to go a step ahead of just speed profiling your site and see how not only how it performs but also how it appears on different browsers, Webpagetest would be the best option for you. Due to its vast range of browsers available (From IE7 to Chrome on Android or even Safari on iOS)
If your website serves visitors only from your own city or country. It'll be a good idea to speed test it using one of Webpagetest's servers in or near to your area.
Considering the fact that a large fraction of people nowadays visit websites from mobile devices, it is very important that your site performs well on mobile browsers too. To help you with increasing your site's performance in the mobile arena, Google Page-speed has you covered, it'll test your site with respect to mobile platforms and provide you a detailed report of your current score and what you can do to improve it.
Even though Google's Pagespeed Insights does quite an amazing job as a speed profiler, currently it doesn't provide you with the option of analyzing your website from a specific location.
Provides unhelpful instructions like "eliminate blocking JS", well duh, but what JS is blocking? Without a waterfall/HAR like the other's GPS is seriously lacking in usefulness.
Once you test your website using Google pagespeed online, it not only gives you a score of how fast your website is, but also what you can do to improve it. These optimization tips can range from minifying assets and optimizing images to leveraging browser caching. Following these you could improve, not only your pagespeed score but also your rank in Google search results
Like all of its competitors GTMetrix also does provide an extremely detailed report of its findings, which include a really useful waterfall feature and the famous and extremely informative YSlow website speed grading as well.
GTMetrix.com have their servers in a number of countries, these give you the freedom to profile your website from the location where most of your traffic originates from
You can see by what margins your results vary when your website's ping is tested from 2 different locations, you can then compare your results with those of your competitors.
Does not provide much of a detailed report, of how your website performed. But again, MaxCDN Tools, as the site's slogan says - is more of a Ping testing and comparison service than a full fledged website speed profiler.
Sometimes, your website is not the only culprit causing an increase in load times, its in such cases that you might require to use features such as DNS Health or Traceroutes, to diagnose the problem.
Pingdom's UI is extremely easy to understand both for beginners (just looking for their overall scores) or nerds looking for in-depth analysis of their pages.
Features HTML validation via W3C, details about used technologies, SERP & Social previews, content summary, page link checks and request map visualization.