YSlow will analize a web page and tell you why it's slow based on Yahoo's rules for high performance web sites.

Here are some key features of "YSlow":

· Performance report card
· HTTP/HTML summary
· List of components in the page
· Tools including JSLint

Requirements:

· Firefox 1.5 - 3.0.*

What's New in This Release: [ read full changelog ]

· Firefox 3 and Firebug 1.2 beta support
· improved and simplified check for javascript minification
· different coloring for inline vs external CSS and JS ("All CSS" and "All JS" features)
· clickable list of resources as a Table of Contents ("All CSS" and "All JS" features)
· improved colors and presentation in the "legend" of component pies under Stats
· fixed a bug where the same hostname with different port number was counted as a separate DNS lookup.
· misc bugfixes and style tweaks