Given the relative ease of writing Firefox extensions, it's not surprising that many have emerged for developers to use while creating web content. These extensions are all useful during the development or repair phase of your content creation. Check back regularly as new extensions surface with regular frequency.

The Firefox browser is an open source web browser that is available for all major desktop and mobile operating systems, although these current plugins are not available for mobile devices. The most recent copy of the browser can be downloaded directly from the Firefox web-site.

Last Updated: June 25, 2011

Web Developer's Toolbar:

Another great tool to add to the arsenal. Developed by Chris Pederick, this extension to Mozilla / Firefox provides a comprehensive toolbar for running quick tests on pretty much everything.

Accessibility Extensions for Mozilla:

accessibilityext.xpi adds features to Mozilla / Firefox to make it easier for people to view and navigate web content based on the structural markup used to create the web page. It can be used by authors to check their structural markup to make sure it matches the actual content structure of the resource.

WAVE Toolbar:

The WAVE Firefox toolbar provides a mechanism for running WAVE reports directly within Firefox. Because the toolbar reports runs entirely within your web browser, no information is sent to the WAVE server. This ensures 100% private and secure accessibility reporting. The toolbar can check intranet, password-protected, dynamically generated, or sensitive web pages. Also, because the WAVE toolbar evaluates the rendered version of your page, locally displayed styles and dynamically-generated content from scripts or AJAX can be evaluated.

Worldspace FireEyes:

Worldspace FireEyes is a nextgen web accessibility tool that ensures both static and dynamic content within a web portfolio are compliant with standards such as Section 508, WCAG 1.0, and WCAG 2.0.

Juicy Studio Accessibility Toolbar:

This excellent Toolbar contains both a Color Contrast evaluator and a Complex Table Inspector. Right-click functionality allows for reporting of these issues.


Accessibar is a toolbar extension for the Mozilla browser which aims at providing various accessibility features for users who could benefit from them. These features primarily focus on the dynamic manipulation of the visual display of the web page in addition to the integration of a text to speech reader which can read out loud the browser's user interface as well as web page content.

HTML Validator (based on Tidy):

HTML Validator is an Mozilla extension that adds HTML validation to Firefox and Mozilla. The number of errors of a HTML page is seen on the form of an icon in the status bar when browsing. The details of the errors are seen when looking the HTML source of the page. Instant feedback, the view source highlights where your problems are, and, using Tidy, allows you to fix them. Excellent!

Mouseless Brousing:

Mouseless Browsing (MLB) means id-based browsing. Major goal of this extension is to enable browsing only by using the numpad keys. Mouseless browsing is based on marking all links, form elements and frames with ids. You can then trigger an action (e.g. following the link) by simply entering the id and depending on the configuration confirming it by pressing Enter.

Sharkware - JAWS Screen Reader Adaptation for Mozilla Firefox:

At long last, JAWS users can now surf the web with the Firefox browser. An Open Source release from the University of Texas Accessibility Institute, this project has resulted in a JAWS script and a Firefox extension that enable JAWS to function with Mozilla Firefox in a similar manner to how JAWS functions with Internet Explorer.


Adds "View Image Longdesc: ..." to the image context menu (obviously only if the image element does have a longdesc attribute set).


FoxyVoice is a Firefox extension that provides text-to-speech functionality using Microsoft Win32 Speech API (SAPI). With FoxyVoice you can listen to the page being read aloud, although it lacks the functionality of a true Screen Reader or Speech Browser. Still in development.


Another Mozilla / Firefox extension for the Windows platform. Fangs creates a textual representation of a web page similar to how the page would be read by one of the modern screen readers. (Still in early development, but may prove to be very useful, especially in teaching/seminar environments.)

Acc - an Accessibility Evaluator

Acc - an Accessibility Evaluator tries to do what other evaluators can't do. It includes basic explicit test for HTML, but also includes features like

  • Visual layout extraction implementation
  • Basic scalability test
  • Deeply nested layout tables test
  • Skip to Main Content link check
  • Navigation consistency check compared to previous page
  • Scripted page evaluation
Section 508 - Accessibility Toolbar:

The purpose of the toolbar is to provide a tool that can assist you in the manual process of checking for U.S. Section 508 compliance of Web sites and Web applications. It has some interesting options I've not seen in other toolbars, including the ability to test "Readability" and some of the document information that it can provide (file sizes, etc.).