How to test website speed and perormance

There is some website/tools which will help you to test your website and performance. It is necessary to speed up your website. After testing your website speed you can take necessary steps to increase your website speed.

Website speed and performance testing website link:
http://tools.pingdom.com/fpt/
https://developers.google.com/speed/pagespeed/insights
http://www.webpagetest.org/
http://www.serverspeed.com/