Manual Testing

While automatic tools that test for accessibility can be helpful, they can also misdiagnose or even fail to find certain problems. Moreover, in some instances human judgment is required to properly assess whether or not accessibility standards have been met. For these reasons, manual testing is a critical part of assessing a website's level of accessibility.

Testing with Assistive Technology (AT)

One of the best ways to verify that a website is accessible is to test it with the same technologies that visitors themselves will use. There are many assistive technologies in common use, but two very important ones are screen readers and screen magnifiers. We recommend that they be used to test all web content to ensure accessibility.

Screen Readers

While visual users experience a web page as a two-dimensional whole, screen readers present pages in linear order based on their structure. By default, they read out the page's content. They usually also have a number of commands that allow for navigating and interacting with properly structured content in more complex ways.

Most visual users find their first experience with a screen reader disorienting, but the basics of using one for testing purposes can be learned easily. Truly mastering all of the functionality that screen readers provide can take much longer, but this is not required for effective testing.

When testing with a screen reader check that:

  • All visible content is read out
  • All active elements are operable from the keyboard
  • The page is properly structured to allow navigation of the content
  • There isn't any "junk" that is invisible to visual users, but can be heard by screen reader users

Some examples of screen readers:

Screen Magnifiers Screen magnifiers are software that allow the user to magnify the screen many times its usual size. Some commercial screen magnifiers also allow users to set colour contrasts, alter pointers, and similar effects that make it easier for users with low vision to read and interact with web pages.

The big challenge for screen magnifier users is that they can only see a small portion of the screen at a time, due the extreme magnification of the text. This can make it harder for them to navigate a page, to either find what they are looking for or even see everything that is available.

When testing with a screen magnifier check for:

  • Inconsistent layout that makes it harder to find things
  • Excessive space between elements that hinder users from finding content on different sides of the page
  • Images (especially of text) that look fuzzy when magnified ZoomText is an example of a commercial screen magnification software. Most operating systems have basic screen magnification functionality built in as well.

Tools to help with manual testing The essential tool for manual testing is of course the browser. A particular site should be tested using the most common browsers, or at least those that are officially supported in accordance with an organization's website policy.

A number of plug-ins or stand-alone tools that can help identify accessibility issues as part of a manual review are available. Below are some examples:

  • Web Accessibility Toolbar for Internet Explorer: This tool offers a number of functions to help find accessibility problem in IE.
  • WAVE Toolbar for Firefox : This is similar to the above tool, but is designed for Firefox.