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Lightning-Fast Web Performance
Online CourseLearn to analyze performance, fix issues, and deliver fast websites from the start.
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Introducing Carbon Control Experimental
New in WebPageTest! Measure your site's carbon footprint and run No-Code Experiments to find ways to improve.
Say hello to 
All of the WebPageTest features you already love, plus API Access & No-Code Experiments!
View Plans & Learn More >>“Experiments are a game changer for quantifying the speed impact of performance optimizations. What took days of technical work is now just a few clicks. Not only will this save tons of time, it will let us test and iterate ideas to find the right mix of recommendations efficiently.
I’m blown away this exists, it feels like magic.”
Real Experience
Test your user’s real experience with global locations, modern devices, and the latest browser versions.
Video Capture
Correlate your user’s visual experience to the technical measurements of your site.
In-Depth Metrics
Dive into the anatomy of your webpage with components like DNS, TCP, TLS, and more.
What's new on the WebPageTest Blog
Recent Industry Blog Posts
- Yielding to the Main Thread: How Breaking Up Tasks Can Fix INP
- Sluggish CATs: Category Pages Have the Worst Responsiveness (INP) on e-Commerce Sites
- Simplifying Web Performance with a single UX score
- Fastest Way of Passing State to JavaScript, Re-visited
- Benchmarking, Profiling, and Optimizing JavaScript libraries