While manual testers fail to test websites for performance, there are two reasons: they don’t have proper tools and they don’s have required skills for performance testing. Then how to succeed? The first thing you need to do is to ask for required tools and train your staff for necessary skills. The tool we will talk about here is called WAPT, which is short for Web Application Load, Stress and Performance Testing. It is a cost effective and easy to learn tool. It has some pros. It is easy to install, and easy to use with very short learning curve. Also you get run-time reports so that you can decide whether to continue the test or not. Meanwhile, it provides detailed test report with graphical representation, supports secure HTTPS protocol, and have 30 days free trial available.
Source: http://www.softwaretestinghelp.com/web-application-load-stress-and-performance-testing-using-wapt/