Gtmetrix

GTmetrix is a free tool that analyzes your page's speed performance. Using Page Speed and YSlow, GTmetrix generates scores for your pages and offers actionable...

Free Web

PageSpeed Insights

PageSpeed is addon for Firebug (debugger addon for Mozilla Firefox ) for analyzing of page loading process and suggesting to webmaster how speed up page loading.

Free Open Source Mac Windows Linux Firebug Chrome ... Firefox

Google Lighthouse

Lighthouse is an open-source, automated tool for improving the quality of web pages. You can run it against any web page, public or requiring authentication.

Free Open Source Mac Windows Linux

Site monitoring

Free open-source website monitoring software, easy to set up and use for monitoring web sites. You can monitor single web pages, multiple web pages, pages in sitemap and...

Free Open Source Mac Windows Linux

WebPagetest

Run a free website speed test from multiple locations around the globe using real browsers (Firefox, IE, Chrome, Android and iOS) and at real consumer connection speeds....

Free Open Source Web

Yellow Lab Tools

Yellow Lab Tools checks a website for both it's performance and the quality of the HTML, CSS and JavaScript code. The application is available online and as...

Free Open Source Web

Yahoo! YSlow

YSlow analyzes web pages and suggests ways to improve their performance based on a set of rules for high performance web pages. YSlow is a Firefox add-on integrated with...

Free Open Source Mac Windows Linux Firebug Chrome ... Safari Opera Firefox

Site Relic

Site Relic is a FREE toolbox where you can test your website for performance & security in seconds without user registration.

Freemium Web

PageSpeedAlarm.com

Be notified if your Google PageSpeed falls.

• Discontinued Now redirects to https://www.orbonline.co.uk/

Free Web

WDT - Web Developer Tools

WDT - Web Developer Tools is a suite of useful tools for web developers Task Manager Dean Edwards Javascript Compressor JSMin Css Minifier Css Type Set...

• Discontinued Last update was on July 7th, 2011.

Free Open Source Mac Windows Linux Python

WebO (Web Optimizer)

This project has been launched after the Russian web conference ClientSide2007. The goal was to gather not only theoretical information about websites speeding-up, but...

Free Web

neXpert

neXpert is an add-on to Fiddler Web Debugger which aids in performance testing web applications. neXpert was created to reduce the time it takes to look for performance...

Free Windows

Omnibug

Omnibug is a plugin for the Google Chrome and Mozilla Firefox browsers to ease developing and debugging web metrics implementations. Each outgoing request (sent by the...

Free Open Source Mac Windows Linux Chrome Firefox

web.dev

With actionable guidance and analysis, web.dev helps developers like you learn and apply the web's modern capabilities to your own sites and apps.

Free Web