PageSpeed can analyze the performance of your webpages and get specific suggestions on how to optimize them.
Install PageSpeed from Chrome web store.
Figure: Install PageSpeed Insights (with PNaCl)
In Developer Tools (F12), you will have a new tab named PageSpeed.
Figure: Start your PageSpeed by clicking "Analyze"
The result of the analysis will be displayed in the PageSpeed tab.
Figure: Some files can be compressed more than 80%