Here is a list of 10 of my favorite website / web page performance testing tools. The tools test things such as load time, load speed and web server stress, many of them provide helpful tips on how to increases website performance.
GTmetrix | Website Speed and Performance Optimization
Broswer Mob Website Performance Test
WebPageTest.org Web Page Performance Test
Pingdom Tools – Test the load time of a web page
Gomez Web Site Performance Test
Web Page Analyzer – 0.98 – from Website Optimization
Benchmark your website or test the speed of your web connection.
Gomez Instant Test Center
Webserver Stress Tool – 30 Day Free Trial Software