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Instantly test your site’s speed, usability, and resilience in real browsers, devices, and locations around the world.

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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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All of the WebPageTest features you already love, plus API Access & No-Code Experiments!

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Start a Site Performance or...

Lighthouse
Visual Comparison
Traceroute

Test!

Enter URL to test

Simple Configuration 3 test runs from recommended location and browser presets

Include Repeat View (Loads the page, closes the browser and then loads the page again)

Run Lighthouse Audit (Runs on Chrome, emulated Moto G4 device, over simulated 3G Fast connection)

Advanced Configuration Choose from all browser, location, & device options

Test Location

Browser 0 Pending Tests

Connection

BW Down	BW Up	Latency	Packet Loss
Kbps	Kbps	ms	%

Desktop Browser Dimensions
Number of Tests to Run
Repeat View First View and Repeat View First View Only
Capture Video
Label

Stop Test at Document Complete
Typically, tests run until all activity stops.
Ignore SSL Certificate Errors
e.g. Name mismatch, Self-signed certificates, etc.
Capture network packet trace (tcpdump)
Save response bodies
For text resources (HTML, CSS, etc.)
Preserve original User Agent string
Do not add PTST to the browser UA string
User Agent String
(Custom UA String)
Append to UA String
Disable AVIF image support
Firefox and Chromium-based browsers only
Disable WEBP image support
Firefox and Chromium-based browsers only
Disable JPEG XL image support
Firefox and Chromium-based browsers only
Capture Full Size Video
Enables full size screenshots in the filmstrip
Minimum test duration
Capture data for at least... seconds
Custom headers Add custom headers to all network requests emitted from the browser (type in or read from a text file)
Inject Script JavaScript to run after the document has started loading (type in or read from a text file)

Chrome-specific advanced settings:

Capture Lighthouse Report (Uses a "3G Fast" connection independent of test settings)
Emulate Mobile Browser
Capture Dev Tools Timeline
Enable v8 Sampling Profiler (much larger traces)
Capture V8 Runtime Call Stats
Capture Chrome Trace (about://tracing)
Trace Categories
(when tracing is enabled)
Capture Network Log
Enable Data Reduction
Chrome 34+ on Android
Use Chrome dev tools traffic-shaping (not recommended)
Host Resolver Rules
i.e. MAP * 1.2.3.4
Command-line
Custom options

HTTP Basic Authentication
Username
Password

PLEASE USE A TEST ACCOUNT! as your credentials may be available to anyone viewing the results.

Enter Script (or read it from a text file)

Script includes sensitive data
The script will be discarded and the HTTP headers will not be available in the results
Discard all HTTP headers

Check out the documentation for more information on this feature

Block Requests Containing (URL substrings)... Space-separated list (type in or read from a text file)

Block Domains (full host names)... Space-separated list of domains (type in or read from a text file)

Simulate failure of specified domains. This is done by re-routing all requests for the domains to blackhole.webpagetest.org which will silently drop all requests.

Hosts to fail (one host per line)... Type in or read from a text file

Custom Metrics: Type in or read from a text file

See the documentation for details on how to specify custom metrics to be captured.

List of URLs to test (one URL per line)...

or
upload list of URLs (one per line):

“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.”

Todd Parker Partner, 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.