Accessibility Rule: Elements must only use supported ARIA attributes

About This Accessibility Rule

The WAI-ARIA specification organizes roles, states, and properties into a strict taxonomy. Each role defines three categories of attributes it can use:

Required attributes — must be present for the role to function correctly.
Supported attributes — optionally enhance the role’s semantics.
Inherited attributes — come from superclass roles in the ARIA role hierarchy.

Any ARIA attribute that doesn’t fall into one of these categories is not allowed on that role. This applies equally to explicit roles (set with the role attribute) and implicit roles that HTML elements carry by default. For instance, <button> has an implicit role of button, <input type="checkbox"> has an implicit role of checkbox, and <h2> has an implicit role of heading.

When an unsupported attribute appears on an element, the result is unpredictable. A screen reader might silently ignore it, or it might announce contradictory information — for example, describing a heading as a checkable control. In the worst case, invalid role-attribute combinations can break accessibility for entire sections of a page.

Who is affected

This issue has a critical impact on people who use assistive technologies:

Screen reader users (blind and deafblind users) depend on accurate role and state information to understand and interact with content. Conflicting ARIA attributes can cause elements to be announced as something they are not.
Voice control users rely on correctly exposed semantics to issue commands targeting specific controls. Misrepresented roles can make controls unreachable by voice.
Users of switch devices and alternative input methods depend on tools that interpret ARIA roles and attributes to identify operable controls. Invalid attributes can make controls appear inoperable or misrepresent their purpose entirely.

When ARIA attributes conflict with an element’s role, these users may encounter controls that lie about what they do, states that never update correctly, or entire regions that become completely unusable.

Relevant WCAG success criteria

This rule relates to WCAG 2.0, 2.1, and 2.2 Success Criterion 4.1.2: Name, Role, Value (Level A), as well as EN 301 549 clause 9.4.1.2. This criterion requires that all user interface components expose their name, role, and value to assistive technologies in a way that can be programmatically determined. Using unsupported ARIA attributes on a role violates this criterion because it introduces properties that conflict with the element’s actual role, breaking the contract between the page and assistive technology.

How to fix the problem

Identify the element’s role. Check for an explicit role attribute. If none is present, determine the element’s implicit ARIA role from its HTML tag. For example, <input type="checkbox"> has an implicit role of checkbox, and <nav> has an implicit role of navigation.
Look up the allowed attributes for that role in the WAI-ARIA specification’s role definitions. Each role page lists its required states and properties, supported states and properties, and inherited properties from superclass roles.
Remove or relocate any ARIA attribute that isn’t in the allowed list. If the attribute belongs on a different element within your component, move it there.
Reconsider the role. Sometimes the right fix isn’t removing the attribute but changing the element’s role to one that supports the attribute you need. If you want a toggleable control, use role="switch" or role="checkbox" instead of role="button".
Consult the ARIA in HTML specification for additional conformance rules about which ARIA attributes are appropriate on specific HTML elements, including restrictions on how elements can be named.

Examples

Incorrect: unsupported attribute on an explicit role

The aria-checked attribute is not supported on role="textbox" because a textbox is not a checkable control. A screen reader might announce this element as both a text input and a checked control.

<div role="textbox" aria-checked="true" contenteditable="true">
  Enter your name
</div>

Correct: unsupported attribute removed

Remove aria-checked since it has no meaning on a textbox. Use aria-label to provide an accessible name.

<div role="textbox" contenteditable="true" aria-label="Your name">
</div>

Incorrect: unsupported attribute on an implicit role

The <h2> element has an implicit role of heading. The aria-selected attribute is not supported on headings because headings are not selectable items.

<h2 aria-selected="true">Account Settings</h2>

Correct: unsupported attribute removed from heading

If selection semantics aren’t needed, remove the attribute. If you need selection behavior, use an element with an appropriate role such as tab.

<h2>Account Settings</h2>

Incorrect: role doesn’t match the intended behavior

The developer wants a toggleable control but used role="button", which does not support aria-checked.

<div role="button" aria-checked="true" tabindex="0">
  Dark mode
</div>

Correct: role changed to one that supports the attribute

Changing the role to switch makes aria-checked valid. The element remains keyboard-operable via tabindex="0".

<div role="switch" aria-checked="true" tabindex="0" aria-label="Dark mode">
  Dark mode
</div>

Incorrect: unsupported attribute on a native HTML element

The <a> element has an implicit role of link. The aria-required attribute is not supported on links because links are not form fields that accept input.

<a href="/terms" aria-required="true">Terms of Service</a>

Correct: unsupported attribute removed from link

Remove aria-required from the link. If you need to indicate that agreeing to terms is mandatory, communicate that through a form control such as a checkbox.

<a href="/terms">Terms of Service</a>

Correct: supported attribute on a matching implicit role

The aria-expanded attribute is supported on the implicit button role, making this combination valid.

<button aria-expanded="false" aria-controls="menu-list">
  Menu
</button>
<ul id="menu-list" hidden>
  <li><a href="/home">Home</a></li>
  <li><a href="/about">About</a></li>
</ul>