ARIA property
aria-multiselectable
Whether more than one option can be chosen at once.
It tells people the widget takes more than one selection before they try to make one. Turn it on and the announcement for the container changes. The children do not change on their own.
Which roles may carry aria-multiselectable
- Value
- true/false
- Filed as
- A property, which is how ARIA files it and not a rule about how often it changes.
- Roles that inherit it
treegrid
Those lists are not advice. Browsers are required to ignore a non-global attribute sitting on a role that does not support it, so aria-multiselectable on the wrong element is not weak, it is absent. You can read it in the DOM and nobody using a screen reader can.
Every role above comes from the specification's own list for this attribute, checked name for name. The normative definition stays with the W3C, in the aria-multiselectable section of the ARIA specification.
Keeping aria-multiselectable true
Getting the children right is the work. The spec asks that in a multiselectable widget every selected descendant carries aria-selected of true and every selectable one carries false, so absence stops meaning maybe and starts meaning not selectable at all. That is a rule about every child, applied every time the list renders. Filter the list, add a row, virtualise the scroll, and any item that arrives without the attribute drops quietly out of the count people hear.
How aria-multiselectable gets checked
There are test rules that check an ARIA attribute is one that exists, is allowed on the role underneath it, and carries a value of the right type. What they map to is ARIA's own author requirements rather than any WCAG criterion, so a misplaced attribute breaks ARIA without being a WCAG failure by itself. It becomes one under 4.1.2 Name, Role, Value the moment the missing or wrong value means the control's state cannot be worked out programmatically, which is what usually happens next.
Nothing automated catches the failure this page is about. A stale value is a valid value, on a permitted role, with the right type. It is only wrong about the world.
Attributes you will meet alongside aria-multiselectable
- aria-errormessage Points at the message explaining why this field is invalid. Only meaningful while aria-invalid is set.
- aria-expanded Whether the thing this control opens is currently open.
- aria-invalid Says a field's value has failed validation.
- aria-orientation Whether a widget runs horizontally or vertically, which decides which arrow keys move through it.
- aria-readonly The value can be read but not changed. Unlike disabled, it is still part of the form.
- aria-required Says a field has to be filled in before the form can be submitted.
Every ARIA state and property · Every ARIA role · ARIA explained