The Attr.localName read-only property returns the local part of the qualified name of an attribute.


name = attribute.localName

Return value

A DOMString representing the local part of the attribute's qualified name.


The following example shows "id" in an alert dialog.

HTML Content

<button id="example">Click me</button>

JavaScript Content

const element = document.querySelector("#example");
element.addEventListener("click", function() {
  const attribute = element.attributes[0];


The local name of an attribute is the part of the attribute's qualified name that comes after the colon. Qualified names are typically used in XML as part of the namespace(s) of the particular XML documents.

Note: In Gecko 1.9.2 and earlier, the property returns the upper-cased version of the local name for HTML attributes in HTML DOMs (as opposed to XHTML attributes in XML DOMs). In later versions, in compliance with HTML5, the property returns in the case of the internal DOM storage, which is lower case for both HTML attributes in HTML DOMs and XHTML attributes in XML DOMs.


DOM Standard (DOM)
# dom-attr-localname

Browser compatibility

BCD tables only load in the browser

See also