Success criteria levels

Remember the guidelines where divided into different success criteria? Nice. Those success criteria are classified into 3 levels.

  • Single-A (A): the lowest
  • Double-A (AA): the medium
  • Triple-A (AAA): the highest

They are similar to the WCAG 1.0 checkpoints’ priorities, but WCAG 2.0 stresses that all success criteria are important: Lowest level enables the access to the webpages, and highest level enables their usability.

To decide which level is each criterion, the WAI has established these questions:

  • Is this success criterion essential? If this criterion not met, the user agents (including assistive technology) cannot reproduce the webpage.
  • Is this success criterion applicable for every website, despite its content, type of content, technology used…?
  • Can the content creators be able to learn how to meet this success criterion? The WAI has establised one week or less to acquire these skills.
  • How will this success criterion limit the functions or “look & feel” of the page? This includes functionality, presentation, freedom of expression (everyone, including not tech-people should contribute), design or aesthetic.
  • Is there an alternative, indirect way if the success criterion is not met?

One great point on WCAG 2 is that they provide an official way of testing each criterion. We will see how can we test them later.

More info