Testing the accessibility of webpages can be challenging. Only a certain percentage of issues can be found with automated tools like WAVE, ANDI, or Axe. It would be convenient if testing tools could find all issues, but in practice some automated checkers are better than others at finding different types of issues. If you want to do a thorough accessibility evaluation, you will likely need to test with several different tools to find the most issues.
Here’s a comparison of issues that various automated accessibility checkers can find:
|
Issue |
|||||
|---|---|---|---|---|---|
|
Language missing |
Yes |
Yes |
Yes |
Yes |
Yes |
|
Iframe missing title attribute |
No |
Yes |
Yes |
Yes, under focusable elements |
Yes |
|
Missing alternative text |
Yes |
Yes |
Yes |
Yes, under Graphics/Images |
Yes |
|
Long alternative text |
Yes |
No |
No |
No |
No |
|
Aria attribute not allowed |
No |
Yes |
Yes |
No |
No |
|
Underlined text (Pseudo links) |
Yes |
No |
No |
No |
No |
|
Skipped heading level |
Yes |
No |
Yes, says Heading elements are not in a sequentially-descending order |
No, under Structures > Headings |
No |
|
Poor text contrast |
Sometimes |
Yes |
Yes, says background and foreground colors do not have a sufficient contrast ratio. |
Yes |
Yes |
|
Missing table headers |
Yes, will call it a ‘layout table’ |
No |
No |
Yes, under tables |
No |
|
Touch targets without sufficient size or spacing |
No |
No |
Yes |
No |
No |
‘Yes’ for the tool can find and ‘No’ for the checker can’t find. ‘Sometimes’ means that the checker sometimes can find the issues but not in all cases. For example, WAVE can check contrast ratios of live text but not in images of text, such as in a logo.
If your organization is using PopeTech as its compliance scanner, the WAVE browser extension is a good tester to start with because PopeTech uses WAVE as it’s accessibility engine. In the table above I’ve compared WAVE to other popular automated testers. ANDI is a nice, lightweight bookmarklet that can find a lot of accessibility issues.
Accessibility Insights offers not only automated testing with the Quicktest, but also can guide you through the steps of a conformance testing methodology. So, if you need to do more through manual testing, Accessibility Insights can guide you through that step by step. The only downside is that it doesn’t always refer to WCAG success criteria (SC) as you go through the steps. It can be a good reference to know what WCAG SC each step is related to.