Web/API/Node/baseURI

The baseURI read-only property returns the absolute base URL of a Node.

The base URL is used to resolve relative URLs when the browser needs to obtain an absolute URL, for example when processing the HTML <img> element's src attribute or XML xlink:href attribute.

In most cases the base URL is simply the location of the document, but it can be affected by many factors, including the <base> element in HTML and the xml:base attribute in XML.

Syntax

var nodeBaseURI = node.baseURI;

Value

A DOMString representing the base URL of the specified Node. It may be null if unable to obtain an absolute URI. Although this property is read-only, its value may change in certain situations (see below).

Details

The base URL of a document

The base URL of a document defaults to the document's address (as displayed by the browser and available in window.location), but it can be changed:

When an HTML <base> tag is found in the document
When the document is new (created dynamically)

See the Base URLs section of the HTML Living standard for details.

You can use document.baseURI to obtain the base URL of a document. Note that obtaining the base URL for a document may return different URLs over time if the <base> tags or the document's location change.

The base URL of an element

The base URL of an element in HTML normally equals the base URL of the document the node is in.

If the document contains xml:base attributes (which you shouldn't do in HTML documents), the element.baseURI takes the xml:base attributes of element's parents into account when computing the base URL. See xml:base for details.

You can use element.baseURI to obtain the base URL of an element.

Specifications

Specification	Status	Comment
DOMThe definition of 'Node: baseURI' in that specification.	Living Standard

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`baseURI`	Chrome Full support Yes	Edge Full support 12	Firefox Full support 1	IE No support No	Opera Full support Yes	Safari Full support Yes	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 4	Opera Android Full support Yes	Safari iOS Full support Yes	Samsung Internet Android Full support Yes

Legend

Full support: Full support
No support: No support