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  • Number

Used in Roles:

  • listitem
  • option

Inherits into Roles:

  • menuitemradio
  • radio
  • treeitem

See Related:

  • aria-setsize


  • integer

Sets or retrieves the current position of an item within a set. Not required if all elements in the set are present in the DOM.

If all items in a set are present in the document structure, it is not necessary to set this attribute, as the user agent can automatically calculate the set size and position for each item. However, if only a portion of the set is present in the document structure at a given moment, this property is needed to provide an explicit indication of an element's position.

The following example shows items 5 through 8 in a set of 16.

<h2 id="label_fruit"> Available Fruit </h2>
<ul role="listbox" aria-labelledby="label_fruit">
  <li role="option" aria-setsize="16" aria-posinset="5"> apples </li>
  <li role="option" aria-setsize="16" aria-posinset="6"> bananas </li>
  <li role="option" aria-setsize="16" aria-posinset="7"> cantaloupes </li>
  <li role="option" aria-setsize="16" aria-posinset="8"> dates </li>

Authors must set the value for aria-posinset to an integer greater than or equal to 1, and less than or equal to the size of the set. Authors should use aria-posinset in conjunction with aria-setsize.

Note  For cross-browser compatibility, always use the WAI-ARIA attribute syntax to access and modify ARIA properties, for example object.setAttribute("aria-valuenow", newValue).


<element aria-posinset="p" ... >
object.setAttribute("aria-posinset",value);var value = object.getAttribute("aria-posinset");

Microsoft Active Accessibility Properties:

  • N/A (represented in the accessible object tree structure or by child ID)

UI Automation Properties: 

  • N/A (represented in automation element tree structure)

UI Automation AriaProperties Property:

  • posinset
More in this category: « aria-owns aria-readonly »