Tools for web accessibility testing


With you can quickly check a webpage for 508 compliance and learn more about how to become 508 compliant across your entire organization


Checks the pre-enhanced version of a web page designed with progressive enhancement against Evaluera's "WCAG 2.0 Level-AA conformance statements for HTML5 foundation markup" making a report that can serve as a broad and easily confirmed WCAG 2.0 Level-AA claim, even for enhanced versions.

A11Y Compliance Platform

Tools, reports and services to help organizations achieve, maintain and defend the accessibility of their organization's websites. Standards and guidelines used includes Section 508, Web Content Accessibility Guidelines (WCAG) & Americans with Disabilities (ADA)


Pronounced « Alix ». Because it's fun. This CSS file intends to warn developers about possible risks and mistakes that exist in HTML code. It can also be used to roughly evaluate a site's quality by simply including it as an external stylesheet. If you want to get involved in this project, be sure to take a look at its wiki. I'll be pleased to read your issues or pull requests! Note that this bookmarklet might take a couple of seconds to load since it basically injects the a11y.css stylesheet within the DOM of the page you're browsing. It might be a bit slow at first because it is being downloaded from GitHub, but it's the price to pay to keep it up-to-date.

Accessibility Developer Tools by Google Accessibility (Chrome)

Adds an Accessibility audit, and an Accessibility sidebar pane in the Elements tab, to your Chrome Developer Tools. - 17 audit rules; most documented at - Sidebar pane in Elements tab provides extra debugging information, for example color contrast values and color suggestions, missing required ARIA attributes, reason for lack of visibility, accessible name calculation information, etc.

Accessibility Viewer

The Accessibility Viewer (aViewer) is an inspection tool for Windows that displays the accessibility API information (MSAA, IAccessible2, UI Automation, ARIA, HTML DOM) exposed by web browsers to the operating system, and thus to any assistive technology (AT) such as screenreaders.

ACE: the Accessible Colour Evaluator

With a user-centered design approach, we developed the Accessible Colour Evaluator (ACE) which enhances web developers’ and designers’ ability to balance aesthetic and accessibility constraints for choosing a website’s colour scheme.


Nice, but not free - Tanaguru is an opensource (AGPL license) website assessment tool. It is dedicated to accessibility (a11y) audits, and focuses on reliability and high level of automation.

NVDA (free screenreader)


Siteimprove monitors your site for WCAG 2.0 accessibility conformance in web content and PDF documents. Our subscription based service offers an intuitive interface, unlimited training and support, customized reporting based on website responsibilities and high priority areas, and CMS integration. is specifically focused on email and email-HTML. It offers a pragmatic and fast insight into accessibility features which are best applicable in email.

ARIA Validator for Chrome

Scans page for WAI-ARIA implementation issues.


ChromeLens is a set of developer tools that allow developers to code websites better suited for the visually impaired. The three tools that are currently available are: Filters to experience a website; Scanners to audit; Trackers to visually show the path

Visual ARIA

Visual ARIA allows engineers, testers, educators, and students to physically observe ARIA usage within web technologies, including ARIA 1.1 structural, live region, and widget roles, proper nesting and focus management, plus requisite and optional supporting attributes to aid in development.


WAVE is a suite of tools for facilitating web accessibility evaluation by providing a visual representation of accessibility issues within the page. There is an online service at, Firefox and Chrome extensions, and an online and installable API engine.

Visolve (color)

Visolve is the software tool that transforms colors of the computer display into the discriminable colors for various people including people with color vision deficiency, commonly called color blindness. The web version and iOS version have the simulation feature that can simulate the appearance of an image for people with color blindness. By using this feature, people with normal color vision can check how color-blind people see a scene or a signage, etc.

Tingtun PDF Checker

Checks PDF documents based on WCAG 2.0. Upload or refer to online documents to generate report with detected barriers and proposed remedies. Tingtun PDF checker is an online, open source tool, used both in practical quality assurance and monitoring of national document quality.

Tingtun Accessibility Checker

Checks web pages based on WCAG 2.0. Reports barriers, their location together with WCAG references and proposed remedies.


Tenon is a one of a kind accessibility testing tool in that it is aimed at offering unprecedented flexibility in tooling for designers developers testers and content authors. Tenon achieves these goals via its API which can be seamlessly integrated into your existing toolset.

AInspector Sidebar (Firefox)

Web accessibility evaluation tool for Firefox based on WCAG 2.0 and ARIA. The Firefox Accessibility Extension is a Firefox toolbar that allows you to inspect every aspect of a web page to determine its accessibility. A helpful toolbar feature is the Text Equivalents menu which allows you to generate lists of elements such as images and links to see whether each are standards-compliant. You can also launch 3rd party applications such as the WC3 HTML Validator and Link Checker services directly from the toolbar. See:

aDesigner (screen reader)

aDesigner, developed by IBM, simulates the experience of visually-impaired individuals so that designers can better understand how a web page is interpreted by screen readers. It has a plenty of features including a summary and detailed report of compliancy to web accessibility guidelines and simulations for blind or low-vision impairment. See:


EvalAccess is a web-based service for testing your website’s accessibility. You can either point to a web page, an entire website, or directly enter your HTML source code. It checks your mark-up against the WC3’s Web Content Accessibility Guidelines (WCAG 1.0) and provides a summary of the number of errors and warnings and a breakdown of each error.

WebAnywhere: A Screen Reader On-the-Go

WebAnywhere is a browser-based web application that works similarly to screen readers such as JAWS. It’s an excellent way to see how a web page is read and navigated by assistive technologies.


Vischeck simulates how a web page or image will look if viewed by people affected with color-blindness. It simulates three types of color-blindness. You can conduct the test by entering a URL or uploading images.

Accessibility Color Wheel

The Accessibility Color Wheel is a web-based tool to help you select the background color and font color. You can enter the hexadecimal values of the colors you want to test, or you can hover over the color wheel to select colors. =

The Colour Contrast Analyser (Firefox)

The Colour Contrast Analyser, developed by Juicy Studio, is a Firefox extension (currently in alpha) that checks all the elements in the Document Object Model for color contrast to insure that content is accessible by people who are color-blind or affected by other visual-impairments. It uses the color and brightness differences algorithm suggested by the WC3 "Techniques For Accessibility Evaluation And Repair Tools" (AERT). Juicy Studio also has other web accessibility evaluation tools such as the Readability Test, CSS Analyser, and Image Analyser.

The TAW Web Accessibility Test

The TAW Web Accessibility Test evaluates your website’s accessibility based on the WCAG 1.0. It marks trouble spots directly on the web page, allowing you to quickly see where the errors are. Clicking on the error/warning indicator will bump you down to a summary of the issue. It’s a great way to visualize the areas of a web page that needs work.

Web Accessibility Toolbar (IE + Opera)

The Web Accessibility Toolbar (WAT) is an extension for Internet Explorer or Opera that offers designers a ton of useful tools and features to help in the analysis of a web page’s accessibility. One helpful feature is the Greyscale (Colour > Greyscale) feature which renders the web page in black in white to help you find low-contrast spots in the design.


Screen reader emulator fro Firefox. This Mozilla Firefox extension creates a textual representation of a web page similar to how the page would be read by a modern screen reader. The extension and source can be downloaded from the SourceForge project page located at