Performance Proxy

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

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

Made for personal experimental use only by Simon Hearne. Contribute on GitHub.

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.