Html meta content type xml

: The metadata element

The HTML element represents metadata that cannot be represented by other HTML meta-related elements, like , , , or .

• , : a element. If the http-equiv is not an encoding declaration, it can also be inside a element, itself inside a element.
• : any element that accepts metadata content.
• : any element that accepts metadata content or flow content.

The type of metadata provided by the element can be one of the following:

• If the name attribute is set, the element provides document-level metadata, applying to the whole page.
• If the http-equiv attribute is set, the element is a pragma directive, providing information equivalent to what can be given by a similarly-named HTTP header.
• If the charset attribute is set, the element is a charset declaration, giving the character encoding in which the document is encoded.
• If the itemprop attribute is set, the element provides user-defined metadata.

Attributes

This element includes the global attributes.

Note: the attribute name has a specific meaning for the element, and the itemprop attribute must not be set on the same element that has any existing name , http-equiv or charset attributes.

This attribute declares the document’s character encoding. If the attribute is present, its value must be an ASCII case-insensitive match for the string «utf-8» , because UTF-8 is the only valid encoding for HTML5 documents. elements which declare a character encoding must be located entirely within the first 1024 bytes of the document.

This attribute contains the value for the http-equiv or name attribute, depending on which is used.

Defines a pragma directive. The attribute is named http-equiv(alent) because all the allowed values are names of particular HTTP headers:

• content-security-policy Allows page authors to define a content policy for the current page. Content policies mostly specify allowed server origins and script endpoints which help guard against cross-site scripting attacks.
• content-type Declares the MIME type and the document’s character encoding. The content attribute must have the value «text/html; charset=utf-8» if specified. This is equivalent to a element with the charset attribute specified and carries the same restriction on placement within the document. Note: Can only be used in documents served with a text/html — not in documents served with an XML MIME type.
• default-style Sets the name of the default CSS style sheet set.
• x-ua-compatible If specified, the content attribute must have the value «IE=edge» . User agents are required to ignore this pragma.
• refresh This instruction specifies:
  • The number of seconds until the page should be reloaded — only if the content attribute contains a non-negative integer.
  • The number of seconds until the page should redirect to another — only if the content attribute contains a non-negative integer followed by the string ‘ ;url= ‘, and a valid URL.

  Pages set with a refresh value run the risk of having the time interval being too short. People navigating with the aid of assistive technology such as a screen reader may be unable to read through and understand the page’s content before being automatically redirected. The abrupt, unannounced updating of the page content may also be disorienting for people experiencing low vision conditions.

  The name and content attributes can be used together to provide document metadata in terms of name-value pairs, with the name attribute giving the metadata name, and the content attribute giving the value.

  See standard metadata names for details about the set of standard metadata names defined in the HTML specification.

  Examples

  meta charset="utf-8" /> meta http-equiv="refresh" content="3;url=https://www.mozilla.org" /> 

  Specifications

  Browser compatibility

  BCD tables only load in the browser

  See also

  Found a content problem with this page?

  This page was last modified on Jul 18, 2023 by MDN contributors.

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  content-type application/xhtml+xml meta tag #418

  content-type application/xhtml+xml meta tag #418

  Comments

  This issue (#135 — content-type value should be allowed for http-equiv attribute of meta tag) was closed in Jan 2012 but since then standards have been updated and I believe makes this issue a valid issue and an bug in ePubCheck.

  Up to Draft 28 (May 2013) the statement was:-
  http://www.w3.org/TR/2013/WD-html51-20130528/document-metadata.html#pragma-directives
  «The Encoding declaration state may be used in HTML documents, but elements with an http-equiv attribute in that state must not be used in XML documents.»

  Which is contradictory as is required to make the intended XHTML5 file. Else it is technically a HTML5 file that is still valid as it accepts the ‘look’ of a XHTML5 file but may not be parsed/validated correctly by XML engines.

  After that (Draft 29 (October 2013) to Current) the statement is:-
  http://www.w3.org/TR/2013/WD-html51-20131029/document-metadata.html#pragma-directives
  «The encoding declaration state may be used in HTML documents and in XML Documents. If the encoding declaration state is used in XML Documents, the name of the character encoding must be an ASCII case-insensitive match for the string «UTF-8″ (and the document is therefore forced to use UTF-8 as its encoding).»

  The text was updated successfully, but these errors were encountered:

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