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  • Repeat View
  • seconds
  • Add custom headers to all network requests emitted from the browser (type in or read)
  • JavaScript to run after the document has started loading (type in or read)

Chrome-specific advanced settings:

(or read it)


Check outthe documentationfor more information on this feature

Space-separated list (type in or read)

Space-separated list of domains (type in or read)

Simulate failure of specified domains. This is done by re-routing all requests for the domains toblackhole.webpagetest.orgwhich will silently drop all requests.

Type in or read

Type in or read

Seethe documentationfor details on how to specify custom metrics to be captured.

“Experimentsare 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.
我blown away this exists, it feels like magic.”

Todd ParkerPartner, Filament Group

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

Full Throttle: Comparing packet-level and DevTools throttling

Learn why packet-level throttling is better than DevTools throttling and the gold standard in accuracy for WebPerf measurements.

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

New Render Blocking Indicator in Chrome and WebPageTest

How to use WebPageTest's render-blocking indicator to improve on one of the most common performance bottlenecks.

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