Comparison of layout engines (XHTML)

The following tables compare XHTML compatibility and support for a number of layout engines. Please see the individual products' articles for further information. This article is not all-inclusive or necessarily up-to-date. Unless otherwise specified in footnotes, comparisons are based on the stable versions without any add-ons, extensions or external programs.

Only XHTML 1.1 is considered. XHTML 1.1 is necessarily XHTML 1.0 Strict with more elements and attributes deprecated. XHTML 2.0 is still a working draft with no layout engine support. XHTML 1.0 and HTML 4 (both served with ) are covered in comparison of layout engines (HTML). The comparison of XML capabilities are covered in comparison of layout engines (XML).

Version number, if possible, is provided for feature that is fully supported. Proprietary extensions are not included.

Media types
The responses when a well-formatted XHTML document is served with different media types. Note that only  is the recommended media type.

KHTML media type notes

 * 1) application/xhtml+xml &mdash; KHTML supports this media type, but processes the document as HTML.
 * 2) application/xml, text/xml &mdash; HTML entities and custom entities defined by custom DTD are not recognized.

Combined profiles
Extending XHTML by combining with other applications of XML (not referring using img/object element).