The ariaLevel property of the Element interface reflects the value of the aria-level attribute, which defines the hierarchical level of an element within a structure.

A string containing an integer.

In this example the aria-level attribute on the element with an ID of main-heading is set to "1". Using ariaLevel we update the value to "2".

<div role="heading" id="main-heading" aria-level="1">
  This is a main page heading
</div>

let el = document.getElementById("main-heading");
console.log(el.ariaLevel); // "1"
el.ariaLevel = "2";
console.log(el.ariaLevel); // "2"

• ARIA: heading role