GTmetrix

Gtmetrix lets you test you test the speed of your website and shows you how and where to optimize your website with the help of their useful graphs and analytics.

GTmetrix allows you to test your page on a real Android device or Simulated Device options

Additional Features

• Adblock Plus – Disable ads on your page and see the performance difference in page load. Great for troubleshooting.
• Connection Throttling – Load your page on various connection speeds to simulate Dial-Up, 2G/3G, DSL or Cable – See how your page performs for a wide range of users.
• HTTP Authentication –  Allow GTmetrix to analyze pages behind HTTP Authentication by passing through credentials.
• Cookie Sessions – Scan pages that require being logged in by inputting cookie session data.
• E-mail Digests – Keep track of all your monitored pages with a weekly digest. Get overviews of all important data in a convenient format.
• White-Labeled PDF – Brand GTmetrix reports with your own company logo and offer insights to your clientele. Only available with GTmetrix PRO
• URL Filtering – Block or only allow specific resources that load on your page.
• API Functionality – Integrate performance testing into your development environment or application. Get more API credits with GTmetrix PRO.

Example for the Podcasting Resources Guide Site

Here is a screenshot of me optimizing this site by tweaking WP Rocket caching plugin.