Accessibility Inspector for WCAG Evaluation

Rulesets

The Rulesets of the OpenA11y Evaluation Library identifies the rules used to evaluate a web page based on the requirements of the version of the W3C Web Content Accessibility Guidelines (WCAG). The “First Step” Ruleset is for people new to accessibility and identifies 27 rules as a stating point for meeting WCAG requirements.

Number of Rules by WCAG Version and Level

Ruleset Level A Level AA Level AAA Total
WCAG 2.0 (2008) 95 21 1 118
WCAG 2.1 (2018) 102 30 4 136
WCAG 2.2 (2023) 103 37 4 144
First Step 22 5 0 27

More about rules, target resources and result values

  • A rule tests target resources for specific accessibility features.
  • Some rules are fully automated and return pass or fail results and messages.
  • Other rules can only identify the need for human judgement to determine whether an accessibility requirement has been met. These return manual check results and messages.
  • If target resources are not found on the page, the rule result is designated as not applicable.
  • If target resources for a rule are hidden, their element results are designated as hidden. Although hidden elements are not evaluated, they are listed at the element results level to enable developers to consider their accessibility if and when they become available to users.
  • Rules also include information on accessibility techniques and links to related resources to help developers understand how to meet the requirements of a rule.