Are you looking for a way to find how much time your website takes to load or do you want to compare your website speed with any other website on net.
You can use http://whichloadsfaster.com/ to verify this. This site gives time in milliseconds. This site also gives recommendations to increase the speed of your site.
The speed of your website and tips to improve to make it faster is also given by Google Speed Test – https://developers.google.com/speed/pagespeed/insights