complementary landmark: must be top level

Rule ID Landmark 19
Definition The complementary landmark must be a top-level landmark.
  • complementary landmarks provide a way to identify sections of a page that may not be considered the main content, but that provide important supporting or related information to the main content.
  • Top-level landmarks are the easiest to find and navigate to using assistive technologies.
Required No for HTML4 Legacy Techniques ruleset mapping
WCAG Success Criteria

1.3.1 Info and Relationships (Level A, Primary Success Criterion)

Rule Category Landmarks
Scope Element
Target Resources complementary landmark
  • aside
  • Use an aside element to define a complementary landmark.
  • If the aside element technique is not being used, a role="complementary" attribute on the container element of the supporting content can be used to define a complementary landmark.
  • When creating the landmark structure on the page, ensure that the complementary landmark is a top-level landmark (i.e., it is not contained within any other landmarks).
Informational Links