This page provides a list of free tools and resources that support accessible web design and development. The list is a work in progress and is updated regularly as tools and resources evolve.
Web and IT accessibility tutorials
- WebAIM Introduction to Web Accessibility
- W3C Accessibility Fundamentals
- UW Training Options
A variety of trainings, workshops, webinars and courses are available for free to UW employees. For more information see Training Options on Digital Accessibility.
Guidelines and standards
- Web Content Accessibility Guidelines 2.1 (WCAG)
This is the latest version of the definitive web accessibility guidelines from the World Wide Web Consortium (W3C), and is theĀ standard supported by Washington State Policy #188 and the UW IT Accessibility Guidelines. - Accessible Rich Internet Applications (ARIA)
ARIA is a W3C specification that provides a way to make dynamic web applications and advanced user interface controls more accessible to people with disabilities. - WAI-ARIA Authoring Practices
This is an essential resource for anyone developing websites or web applications. It provides standard design patterns for dozens of common web widgets such as accordions, dialogs, and menus.
Browsers’ Built-in accessibility tools
Modern versions of major browsers have their own accessibility tools built into their developer tools. For more information, see the documentation for the tools available in your preferred browser.
- Chrome DevTools Accessibility Reference.
- Firefox Accessibility Inspector
- Microsoft Edge DevTools: Accessibility
Third-party accessibility checkers & browser extensions
The following tools are listed alphabetically.
- Accessibility Bookmarklets
This suite of bookmarklets can be used in any browser and work by visually highlighting specific accessibility features within a web page, including ARIA landmarks, headings, lists, and accessibility-related features of images and forms. - Accessibility Insights
This robust accessibility checker and educational tool from Microsoft is available as an extension for Chrome or Edge, or as downloadable software for checking Windows applications. - AInspector WCAG Firefox Extension
This extension was developed from the same team at the University of Illinois who created the Functional Accessibility Evaluator (FAE), listed below. - axe
This accessibility testing toolkit from Deque (accessibility consultancy) is available as an API that can be integrated into automated testing processes for web development. Android Accessibility is also available as well the axe Chrome Extension. - Functional Accessibility Evaluator (FAE)
This is an online web accessibility evaluator from the University of Illinois. FAE is capable of crawling a website and providing a summary report, plus reports for each individual page. - Siteimprove Accessibility Extensions
The Siteimprove Accessibility Extensions are free and can check any web page for accessibility issues at any given time. All analysis is done entirely within the browser, allowing secure evaluation of password-protected or non-public pages, multi-step forms, and dynamic content. - WAVE
Developed by WebAIM, this online tool evaluates the accessibility of a web page and shows results using icons and indicators, embedded onto the original page. It’s available as a standalone website, or as the WAVE browser extension for both Chrome and Firefox. - Web Developer Extension for Firefox or Chrome.
This highly useful toolbar from Chris Pederick is packed with features, including many that help check web pages for accessibility features.
Code validators
Having valid code is a first step toward web accessibility and cross-browser compatibility. The following tools should be used regularly for checking the validity of your code.
- HTML Validator – from the W3C
- CSS ValidatorĀ – from the W3C
- HTML Tidy
This is a software library that evaluates and cleans up HTML, automatically generating a reformatted (i.e., “tidied”) version. HTML Tidy is widely available, and is integrated into many web coding applications as documented on their website. - HTML Validator Browser Extensions – for Chrome and Firefox, based on HTML Tidy and OpenSG, includes accessibility checks that can be toggled on via the Options menu
- WebVTT Validator – for validating timed text files to be used with HTML video, e.g., for captions, subtitles, chapters, and descriptions.
Color checkers
The W3C’s Web Content Accessibility Guidelines 2.0 requires a specific contrast ratio between foreground and background colors. There are several tools available for measuring contrast:
- Colour Contrast Analyser
This free application, available in Windows and Mac versions, makes it easy to check foreground & background color combinations. Both versions include an eyedropper tool for easily grabbing a particular color from anywhere on the screen. - WCAG Contrast Checker for Firefox
This Firefox extension displays color contrast ratios in a sidebar, and flags the color combinations that fail WCAG contrast requirements at various levels. - WebAIM Color Contrast Checker
This handy online tool includes a feature to “lighten” or “darken” existing colors until you find a combination that meets WCAG 2.0 requirements. This functionality is also built into the WAVE Extension (see WAVE under “Third Party Accessibility Checkers & Browser Extensions”).
Mobile development
- Accessibility for Apple Developers
Apple’s site includes a variety of resources for iOS developers. - Accessibility for Android Developers
Includes a variety of resources that help developers to use the Android framework to make applications more accessible.
Assistive technologies
When testing web pages and IT products with assistive technologies, it is important to be aware that no two assistive technology (AT) products are alike. Developers are cautioned to use these tools only as an approximate gauge of accessibility. What seems to work perfectly in Product A may be inaccessible in Product B. Therefore, developers should resist the tendency to develop sites and applications that work with a particular AT product, and focus instead on developing sites that comply with standards.
Some assistive technology vendors provide demo versions of their products, some of which can be used indefinitely but time out after a few minutes of operation. Product licenses vary as to whether using these demo versions is permissible for testing and development purposes. For information about available products and license restrictions, contact the Access Technology Center.
Also, all major desktop operating systems are bundled with basic assistive technology utilities. For more information about these utilities in Windows and Mac OS X consult the Microsoft Accessibility and Apple Accessibility websites respectively.
In addition, the following assistive technologies can be useful for testing web pages.
- NVDA
NVDA (“Non-Visual Desktop Access”) is a free, open source screen reader for Windows. WebAIM publishes a handy guide on Using NVDA to Evaluate Web Accessibility. - VoiceOver
VoiceOver is Apple’s screen reader, which ships with Mac OS and iOS devices such as the iPhone and iPad. WebAIM publishes a handy guide on Using VoiceOver to Evaluate Web Accessibility. - JAWS (not free)
Although not free, JAWS has been the most popular screen reader for many years (though is now being challenged by NVDA according to the most recent WebAIM Screen Reader User Survey). WebAIM also publishes a handy guide on Using JAWS to Evaluate Web Accessibility.
Web and IT accessibility resources from DO-IT
The DO-IT Center (Disabilities, Opportunities, Internetworking, and Technology) at the UW has worked tirelessly since 1991 to increase the participation of people with disabilities in challenging academic programs and careers. In doing so DO-IT has developed a number of resources related to IT accessibility, including the resources listed below.
- 30 Web Accessibility Tips
Practical tips based on common web accessibility issues encountered in higher education, developed as part of the AccessComputing project, with funding from the National Science Foundation. - Accessible Technology
A collection of publications and videos on various aspects of assistive and accessible technology.