Examine, edit, and debug HTML, CSS, and JavaScript on the desktop and on mobile.

Firebug is described as 'Integrates with Firefox to put a wealth of web development tools at your fingertips while you browse. You can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page' and is a leading Web Debugger in the development category. There are more than 10 alternatives to Firebug for a variety of platforms, including Windows, Mac, Linux, Mozilla Firefox and Google Chrome apps. The best Firebug alternative is Firefox Developer Tools, which is both free and Open Source. Other great apps like Firebug are Google Chrome Developer Tools, Tiny JavaScript Debugger, HTTP Debugger and Domsignal.
Examine, edit, and debug HTML, CSS, and JavaScript on the desktop and on mobile.

The Google Chrome Developer Tools provide an integrated environment for debugging, optimizing, and understanding a web application, or website, running in Google Chrome. The developer tools are developed partly through the WebKit open source project, where the tools are called...



TinyJSD is a JavaScript debugger for privileged code running Mozilla products like Firefox, Thunderbird, SeaMonkey. It serves to debug the application as well as extensions written in JavsScript.

HTTP Debugger Pro - A Professional HTTP Sniffer and Analyzer for Developers.




Domsignal is an all-in-one platform dedicated to empowering developers, SEO experts, sysadmins, and security researchers in their quest for website excellence. We provide a comprehensive suite of tools to help you analyze and optimize your website's performance, security...



SplineTech JavaScript Debugger is the fastest independent standalone JavaScript Debugger that enables you to debug JavaScript for IE completely independently of any add-ons, plug-ins, Java or any other third-party proprietary tools.

HttpWatch is an HTTP viewer and debugger that integrates with IE and Firefox to provide seamless HTTP and HTTPS monitoring without leaving the browser window. It's available as a free edition and a PRO version that cost money and has additional features.

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 browser) is checked for a pattern; if a match occurs, the URL is displayed and decoded to show the details of...



DOMScope is an online web inspector and debugger for mobile web apps. Like Chrome's DevTools, it allows developers to navigate through the HTML, list applied CSS styles and execute JavaScript code inside any device's browser.




HttpFox monitors and analyzes all incoming and outgoing HTTP traffic between the browser and the web servers.


Venkman is the code name for Mozilla's JavaScript Debugger. Venkman aimed to provide a powerful JavaScript debugging environment for Mozilla based browsers.

Almost the same functionality as Firebug, with a lot of improvements.