Google's 'PageSpeed Insights' tool
While poking around online I came across Google's 'PageSpeed Insights' tool. What is this? From their about page, they say "PageSpeed Insights analyzes the content of a web page, then generates suggestions to make that page faster."
Try it on your site here:
The PageSpeed Score ranges from 0 to 100 points. A higher score is better and a score of 85 or above indicates that the page is performing well. Please note that PageSpeed Insights is being continually improved and so the score will change as we add new rules or improve our analysis. The full 'About' page is here: