Web browsers come in all shapes and sizes, all with different features, some better than others.

We’ve tried and tested them all but in our opinion Mozilla Firefox is the clear winner, beating all other browsers on every level.

Not only is Firefox fast, it has excellent plugin functionality and customisability features which increase efficiency beyond belief.

The following list contains a combination of Firefox plugins that we use on a daily basis and some general industry favourites.

If we’ve missed something, please feel free to share it in the comments box at the bottom of this page.

SEO for Firefox

A big pat on the back to Aaron Wall at SEO Book for creating this plugin – we’re regular users and find it incredibly useful.

Undoubtedly one of the best SEO plugins available for Firefox, SEO for Firefox pulls in key marketing data right to your search results allowing you to analyse competitors from your SERP.

Some of the data provided includes Google PageRank, page age, links, number of Delicious bookmarks, Technorati links, Alexa rank, cached pages, dmoz, Bloglines subscriptions, Yahoo! Directory listings and Whois data.

The ‘SEO Xray’ feature allows you to quickly view the SEO aspects of a page, making it a great tool for reviewing webpages.

You can download this plugin for free by creating a SEO Book account.

Click here to download SEO for Firefox

Rank Checker

This is another great little plugin from SEO Book. It allows you to keep up with your keyword performance by checking rankings on Google, Yahoo and Bing.

You can easily import keywords in bulk and export results to CSV. Handy.

Click here to download Rank Checker

SeoQuake

SeoQuake allows you to investigate a wide range of SEO parameters on the fly.

General parameter information includes Google PageRank, Google Index and Google links as well as similar parameters from other major search engines. There is also a tool to create custom parameters.

Click here to download SeoQuake

Firebug

With Firebug you can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page.

This plugin is extremely useful to check if best practice, SEO-friendly coding has been used on any given page. The ability to edit page code and content means you can create ‘before and after’ images of changes that you suggest to a site. Great for reports and reviews.

Check out getfirebug.com for a complete overview of features.

click here to download Firebug

Web Developer

Hugely popular with web developers and SEOs alike, Chris Pederick’s Web Developer is a must-have toolbar.

From an SEO perspective, Web Developer is a great tool for analysing webpages. Various toolbar options allow you to dissect webpages and highlight headings as well as both external and internal links.

Click here to download Web Developer

SearchStatus

SearchStatus displays Google PageRank, Alexa rank, Compete ranking and SEOmoz Linkscape mozRank anywhere in your browser, along with a keyword density analyser, keyword/nofollow highlighting, backward/related links, Alexa info and other SEO information.

Click here to download SearchStatus

HTML Validator

HTML Validator adds HTML validation inside Firefox. The number of errors in a HTML page is shown as an icon in your status bar when browsing and are detailed in the HTML source of the page.

Click here to download HTML Validator

SEOpen

SEOpen provides a selection of basic SEO tools Including Google & Yahoo backlinks, Google PageRank, http header viewer and more.

Click here to download SEOpen

Autofill Forms

One for all the link builders out there, Autofill Forms is a tool that enables you to fill out forms or directories with a single click or  keyboard shortcut.

A useful, time saving tool when working on directory submissions.

Click here to download Autofill Forms

Screengrab

Not an SEO tool per se but worthy of a mention, Screengrab is an incredibly useful extension for reporting or review purposes.

It captures entire web pages and saves them as images, even content below the fold.

It’s a little buggy and by no means unique, but useful none the less.

Click here to download Screengrab