Test accessibility at key stages

Process oriented Tester Frontend developer

Test using the following methods:

  • Automatic accessibility testing
  • Expert based testing
  • User testing

Do short task-based sessions and focus attention on one aspect at the time, e.g. how accessible the forms are.

Key stages for testing are every time something new and essential to the application is developed during the:

  • Designing phase (Start testing with sketches and work your way from there)
  • Development phase (Use automatic testing tool from your first HTML line)

All the different ways of testing for accessibility described below should be applied throughout the process.

Automatic tools

Table 3 gives an overview of some automatic tools for testing accessibility and their functionalities.

Tool Examines data tables Checks structure Checks alt-text Checks labels Checks contrast Examines WAI-ARIA Simulates screen reader Usable on local/password protected sites
Web Accessibility Evaluation Tool (WAVE) No Yes Yes Yes No No No No
WAVE Toolbar for Firefox No Yes Yes Yes No No No Yes
Accessibility Evaluator for Firefox No Yes Yes Yes No No No No
Web Accessibility Checker No Yes Yes Yes No No No No
WCAG Contrast Checker for Mozilla No Yes Yes Yes Yes No No No
WebAim Colour Contrast Checker No No No No Yes No No No
Juicy Studio Accessibility Toolbar Yes No No No Yes Yes No No
Fangs Screen Reader Emulator for Firefox No No No No No No Yes No
Firefox Accessibility Extension Yes Yes Yes Yes Yes Yes No No
Web Accessibility Toolbar (WAT) Yes Yes Yes No Yes Yes No No

Table 3: Automatic testing tools and their functionalities

Expert based testing

There are many different ways of doing expert based testing. The most common ones are:


Simulation is used to simulate what it would be like to use an application with some kind of disability. There are several ways of simulating:

Turning of the following things in the browser:

  • Style sheets
  • Images
  • Sound
  • JavaScript
  • Java
  • Support for Flash/Silverlight
  • Pop-up windows

Be aware that it might be difficult to turn of JavaScript in new browsers.

Navigate using only the keyboard. Try out a few familiar websites first to get used to keyboard navigation. Be aware that and it might be difficult to turn on keyboard access in new browsers.

Turn off the display and navigate the application using a screen reader. Possible screen readers to test with are:

  • Apple screen reader (free software)
  • VoiceOver
  • Demo version of JAWS or the
  • NVDA for Windows (free software)
  • Firefox Screen-reader simulator

User testing

User testing with people with disabilities is a bit different from user testing with users without disabilities. To ensure the highest possible quality of the testing keep this in mind:

  • User may be dependent on large equipment of AT (e.g. Braille keyboard, foot mouse)
  • User should use their own equipment which they are comfortable with
  • User might need to perform the testing in their home or workplace (but they might also be perfectly able to come to a testing facility

Be aware that the tasks need to be the same, but there might be some differences in communication, e. g. saying choose link instead of click on link, talk about content rather than colour, or structural placement rather than visual placement.

Log all accessible script modules

Make sure you log all well functioning and accessible script modules. It facilitates accessibility in the future through reuse.