Test. Optimize. Repeat.
Test your user’s real experience with global locations, modern devices, and the latest browser versions.
Correlate your user’s visual experience to the technical measurements of your site.
Dive into the anatomy of your webpage with components like DNS, TCP, TLS, and more.
Why First Contentful Paint Doesn't Work As a Cross-Browser Metric
Learn why First Contentful Paint isn't exactly apples-to-apples from one browser to the next
WebPageTest API Review on CSS Tricks
Chris Coyier takes the API out for a spin and shares where he sees the most promise for developers
Recent Industry Blog Posts
- Safe DOM manipulation with the Sanitizer API
- How Renault improved its bounce and conversion rates by measuring and optimizing Largest Contentful Paint
- Building a multi-select component
- Bringing instant page-loads to the browser through speculative prerendering
- Best practices for using third-party embeds