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HTML <html> xmlns Attribute

❮ HTML <html> tag


A simple XHTML document, with the minimum of required tags:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

<html xmlns="http://www.w3.org/1999/xhtml">
<title>Title of the document</title>

The content of the document......

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Definition and Usage

The xmlns attribute specifies the xml namespace for a document.

Note: The xmlns attribute is required in XHTML, invalid in HTML 4.01, and optional in HTML5.

Note: The HTML validator at http://w3.org does not complain when the xmlns attribute is missing in an XHTML document. This is because the namespace "xmlns=http://www.w3.org/1999/xhtml" is default, and will be added to the <html> tag even if you do not include it.

Browser Support

xmlns Yes Yes Yes Yes Yes


<html xmlns="http://www.w3.org/1999/xhtml">

Attribute Values

Value Description
http://www.w3.org/1999/xhtml The namespace to use (for XHTML documents)

❮ HTML <html> tag