How to test for website speed and performance using GTMetrix

Website page speed is one of the most important ranking metrics. A recent study from Google showed 53% of website visits would result in a bounce if a website loads in more than 3 seconds. Every additional 1 second of loading delay causes 11% fewer page views and 7% fewer conversions.

Testing for page speed is important and using the right tool helps you understand the real speed of the website. There are a few tools out there to test page speed including GTmetrix, Pingdom, and PageSpeed Insights.

It’s important to understand how each tool works before relying on them for testing. We did extensive research on Pingdom, GTmetrix, and PageSpeed Insights. We have a preference to use GTmetrix because of the following features:

  • Connect Speed options (LTE, Broadband, Etc)
  • HTTP/2 Support
  • Multiple Test Resolutions
  • Simulated Devices (iOS, Windows, Mac, Etc)
  • Consistent hardware provisions for every test location
  • Historical tracking and comparison

GTmetrix displays a PageSpeed Score (Google Standard) and a YSlow Score (Yahoo Standard) to help optimize websites for the two primary standards. Plus the site shows the recommendations from PageSpeed and YSlow, along with a waterfall of how long every item on the page took the load.

GTmetrix Waterfall Chart

GTMetrix helps us optimize websites

Any website we build or host, we perform WordPress site speed optimization. We want to get websites under 3-seconds as recommended by Google and aim for a PageScore of 90 or above.

GTMetrix helps us identify which images are too large, resources that return a 404 error and if we need to add a CDN to the website. We use a few plugins including WP-Rocket, Automatize, and WP-Smush. These plugins allow us to serve scaled images efficiently, leverage browser caching, minify CSS/HTML, and make the site as optimized as possible.

While we found these plugins effective and the simplest way to improve the performance of a WordPress website, this combination of plugins can often find break functionality, so we always review after activating the plugins. After, we test the site on GTMetrix and find out the other opportunity areas.