1. Firebug 1.05 - With this helpful little add-on, you can tweak and monitor CSS, inspect and edit HTML, debug, visualize CSS metrics, monitor your network and also make changes in JavaScript live in any web page. Install Now

2. Google Global Firefox Extension - As results for Google differ from one country to another, results become limited. The end to this problem is Google Global. Install Now

3. Google Webmaster Tools External links ++ - With Google Webmaster Tools External links ++ you can check the PR of the pages linking to you and the anchor text used on the link. This Greasemonkey script determines PR for the link through an XML HTTP request and adding it in front of the link. You need to have Google Webmaster Central Account and the site added and verified in it. Install Now

4. LinkChecker 0.6.1 - With LinkChecker, you can check webpage links at a glance with simple color coding. Ditch those massive listings of bad links that provide no context and add LinkChecker to your arsenal of web development tools today. Install Now5. RankQuest SEO Toolbar 3.9.1 - RankQuest SEO(Search Engine Optimization) Toolbar provides you quick access to more than 30 intuitive SEO tools. Alexa Rank and Page Rank provided by Alexa and Google respectively ensures the popularity of the site. Once you download and install the SEO Toolbar you are only one or two clicks away from carrying out most of your day to day SEO operations. available in Japanese, Italian, Polish, Spanish, Swedish, German, Dutch, French and Chinese languages. Install Now

6. SearchStatus 1.21 - Display the Google PageRank, Alexa rank and Compete ranking anywhere in your browser, along with fast keyword density analyser, keyword/nofollow highlighting, backward/related links, Alexa info and other SEO tools. In simple words, you can check how any website, no matter where in the world, is performing. Install Now7. SEOpen 0.8 - Provides some basic tools to help with search engine optimization. Including google backlinks, yahoo backlinks, PageRank check, http header viewer, and more. Install Now

8. Server spy 0.1.2 - Server Spy indicates what brand of HTTP server (eg. Apache, IIS, etc.) runs on the visited sites. When a tab is selected, the corresponding server name is shown on the right-hand side of the browser's status bar.Install Now

9. Web Developer extension - The Web Developer extension adds a menu and a toolbar to the browser with various web developer tools. It is designed for Firefox, Flock, Mozilla and Seamonkey, and will run on any platform that these browsers support including Windows, Mac OS X and Linux. Install Now

10. X-Ray 0.8.1 - With X-Ray 0.8.1, without viewing the sourcecode, you can see the tags on a page. One installed the X-Ray command is available by right-clicking as well as in the Tools menu. When applied to a page it can help you see how the document was constructed without having to go back and forth between the sourcecode and the page in your browser. Is that list made of li, dd or p elements? Is that an h3 tag or just some bolded text? X-Ray shows you what's beneath the surface of the page . Install Now

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