There's a wide range of tools to support checking accessibility during development and content authoring, and this page lists a selection. These tools come in varying formats and for varying purposes:
- Some tools support checking single accessibility issues, others can check a range of issues at one time.
- Some are automated tools that can be set to rapidly analyze code of many pages for specific issues, and generate reports on results. Other tools are intended to support manual inspection and have features that are useful both for content authors and for developers.
- Browser toolbars can group together a selection of tools to support accessibility checking.
Don't forget that you'll already have some powerful tools available to support accessibility testing:
- Operating system settings can be configured to assess specific accessibility barriers, for example Windows High Contrast Mode.
- Browser DOM inspection tools are very helpful for checking specific accessibility issues, so make good use of these during accessibility testing.
- On Mac OSX and iOS you also have a very powerful screen reader, VoiceOver, which can be used for specific accessibility checks.
Harvard-licensed accessibility testing tools
Harvard has purchased two accessibility testing tools that can be leveraged by faculty and staff who develop and/or support websites or applications. These tools are described below.
- Siteimprove is best-used for public-facing websites. Reports are automatically generated on a weekly basis. Harvard’s license also includes QA tests of broken links, misspellings, etc. and a report of QA issues is also sent weekly.
- Accessibility Management Platform (AMP) from the Level Access (formerly SSB Bart Group) is designed for use with complex, transactional websites and applications. Users schedule tests and reports themselves.
These tools support inspecting for specific accessibility barriers.
Tools for checking color issues, including color contrast problems:
- Colour Contrast Analyser, by The Paciello Group
- Colour Contrast Check, by Jonathan Snook
- Contrast Ratio Checker, by Lea Verou
- WCAG Contrast checker by Jorge Rumoroso (Firefox Extension)
- Contrast-Finder by Tanaguru.
- Accessibility color wheel by Giacomo Mazzocato. Color pair selection tool; also simulates three common variations of of color blindness.
Tools for checking text resizing issues:
Most browsers now support page zoom rather than text resizing, so to test specifically issues relating to support for resizing text may require an additional tool.
- Zoom Page WE (Firefox extension)
Tools for checking specific aspects of code quality:
- Accessibility Viewer, by The Paciello Group. For checking for presence and quality of name, role and value/state information
- Inspect, by Microsoft, for checking accessibility information of a user interface element.
- HeadingsMap by Jorge Rumoroso (Firefox Extension) generates a document map with headings and/or with sections in HTML 5.
- Nu HTML Checker. A code validator from W3C. Note that valid code does not on its own guarantee accessibility.
- PDF Accessibility Checker. A tool for checking PDF documents for structural quality.
Tools for checking multimedia:
- Photosensitive Epilepsy Analysis Tool (PEAT). From the TRACE Center at the University of Wisconsin, Madison. Checks the flicker rate of flickering and flashing content.
Browser toolbars and extensions
These bring together a wide range of specific tools in one place, including tools for highlighting headings, lists and table headers, focus order, and alternative text for images. They provide tools that are of use both to content authors and to developers.
- Web Accessibility Toolbar, by The Paciello Group. A collection of tools for checking a range of accessibility issues. Available for Internet Explorer.
- Accessibility Developer Tools by Google Accessibility (Chrome Extension): Adds an Accessibility audit, and an Accessibility sidebar pane in the Elements tab, to your Chrome Developer Tools
- The Wave toolbar by WebAIM. Available for Chrome.
- Web Developer Toolbar, by Chris Pederick. Includes some tools useful for accessibility checking. Available for Chrome, Firefox and Opera.
- Diagnostic.css, by Karl Groves. This is not a browser toolbar as such, but a CSS file that, when applied, will highlight specific potential accessibility issues on a page.
Automated tools for large-scale accessibility checking
There are many automated accessibility checking tools available, and the most useful are those that can be configured and integrated into existing development and testing processes, to rapidly and reliably check for specific issues in code. Be aware that automated tools can only ever check for issues that can be confidently identified as actual accessibility issues, or flag potential issues that require manual checking.
- SortSite Desktop: Application (for Windows and OS X) for checking web sites for accessibility issues.
- Tenon: provides an API that allows developers to integrate a wide range of reliable accessibility tests into their development workflow.
- AChecker by Inclusive Design Research Centre. Allows users to create their own guidelines, and author their own accessibility checks.
- Opquast Reporting (in French). Website quality and accessibility assessment tool. It includes features to evaluate manually and automatically, to export audit reports in various format, to create tasks from bugs found during the evaluation.
- Tanaguru. An open source (AGPL license) website assessment tool, with a focus on accessibility.