How to read a WebPageTest waterfall chart

On 9th February 2021 at How to read a WebPageTest waterfall chart as part of February – Waterfalls and Bundles…

WebPageTest (WPT) is the goto tool when it comes to analysing, and ultimately fixing web performance problems with a website.

Much of the power of WPT comes from its waterfall chart visualisation.

At first sight it can be confusing to understand, but once mastered it will add a whole new dimension to the data that WPT gives you. This in turn will allow you to make improvements to your website that will really benefit your users.

In this talk Matt will to go over some of the basics of the waterfall chart, as well as delving into some of the more advanced topics.

Hopefully giving you a foundation for future exploration of this incredible tool.

Session video

Presented by

Matt Hobbs

Head of Frontend Development, GDS


Matt Hobbs is Head of Frontend Development at the Government Digital Service. An experienced frontend developer, he is passionate about using his skills to build accessible and performant user interfaces. Matt makes a point of keeping on top of the latest technology and tools, is interested in all aspects of interface development, and is a keen advocate for best practice.


February – Waterfalls and Bundles…


9th February 2021

Skill level

Beginner / Intermediate