The success criteria are testable statements grouped into three levels of conformance:
  - Level 1
 
    - Achieve a minimum level of accessibility, can reasonably be applied to all Web content.
 
  - Level 2
 
    - Achieve an enhanced level of accessibility, can reasonably be applied to all Web content.
 
  - Level 3
 
    - Achieve additional accessibility enhancements, can not necessarily be applied to all Web content.