Performance Proxy

Enter a URL and select performance optimizations, a resulting URL will be generated for testing.

Cross-origin images will not be optimized. Failure is probable with all optimizations. Test with Chrome for most reliable results.

URL Target URL:

Feature Toggles

Advanced Features Add fetchpriority="low" and loading="lazy" by querySelector (each on a new line) Add fetchpriority="high" and loading="eager" by querySelector (each on a new line)

Injections (each on a new line) Top of <html>
Top of <head>
Bottom of <head>
Top of <body>
Bottom of <body>
Response Headers

Request Blocking Block URLs containing (space separated)
Block Hosts containing (space separated)

Direct Testing Test URL:

Visit page in a new tab (note that you may see cross-origin errors accessing directly)

WebPageTest Script

Open WebPageTest. Read more about WebPageTest scripts here.