<$0>
+ is not allowed after the end tag </body>.The start or end tag of an element appears after the
+ body element has been closed. The document is
+ non-conforming.
Any content of the document other than head
+ contents and comments must be put into the body
+ element.
& character must
@@ -63,6 +78,45 @@
</ string is not followed
+ by a tag name.There is a < (U+003C
+ LESS-THAN SIGN) character
+ immediately followed by a / (U+005F
+ SOLIDUS) character, which is not part
+ of any end tag, in the input stream. The document
+ is non-conforming.
The </ sequence immediately followed
+ by an EOF is
+ interpreted as a string data of </.
The </ sequence as string data must
+ be escaped as:
+
</< character is not followed
+ by tag name or by a ! character.A < (U+003C
+ LESS-THAN SIGN) character which is not part
+ of any markup appears in the input stream.
The < character as a data character must
+ be escaped as:
+
<The string &# must be the first two characters
- NUMBER SIGN) character must be the first two characters
of a reference:
To represent &# as data characters, use
- named entity reference:
+ a named entity reference for the & character:
&#To represent &#x as data characters, use
- named entity reference:
+ a named entity reference for the & character:
&#x</ string is not followed
+ by a tag name.There is a < (U+003C
+ LESS-THAN SIGN) character
+ immediately followed by a / (U+005F
+ SOLIDUS) character, which is not part
+ of any end tag, in the input stream. The document
+ is non-conforming.
The </ sequence not followed by a
+ tag name is parsed as an opening of bogus comment.
The </ sequence as string data must
+ be escaped as:
+
</-- sequence
+ in a comment.There is a - (U+002D
+ HYPHEN-MINUS) character
+ at the end of the comment or a -- sequence
+ in the comment. The document is non-conforming.
Comments cannot contain a string --, as in XML.
+ Unlike SGML, there cannot be more than one comments
+ (where comment is an SGML term) in the comment
+ declaration.
$0.There are more than one attributes with the same name in a tag. The document is non-conforming.
@@ -150,6 +243,36 @@<?...?>) cannot be used.Processing instructions (<?...?>),
+ including XML declaration (<?xml ...?>)
+ and XML style sheet PI
+ (<xml-stylesheet ...?>), are not allowed
+ in the HTML syntax. The document is non-conforming.
If it is necessary to embed a processing instruction + in the HTML document, you must use the XML syntax instead.
+ +In the HTML syntax, XML declaration is not necessary.
+ +Instead of XML style sheet,
+ PIs, you must
+ use the HTML link element whose rel
+ attribute is set to stylesheet (or
+ alternate stylesheet for an aleternate style sheet).
Web browsers will parse processing instructions as bogus + comments. Some legacy Web browsers, such as IE:mac and + some mobile browsers, will display processing instructions + as string.
+DOCTYPE appears after any
+ element or data character has been seen.A DOCTYPE appears after any element or data character
+ has been seen. The document is non-conforming.
The DOCTYPE must be placed before any
+ tag, reference, or data character. Only white space characters
+ and comments can be inserted before the DOCTYPE.
HTML a elements cannot be nested.
+ The document is non-conforming.
In the HTML syntax, a start tag of the a
+ implies the end tag of any opening a element.
<$0>
- is not allowed in table.body element.
The start or end tag of an element appears in table.
+
The start or end tag of an element, which
+ cannot be a descendant of body element, appears
+ in the input stream while the body element has been opened.
The document is non-conforming.
<head>
+ is not allowed in the head element.There is a start tag <head> in the
+ <head> element. The document is non-conforming.
In an HTML document there must not be more than
+ one head element, therefore no more than one
+ start tag <head> can appear in the input stream.
<$0>
+ is not allowed in a table element.The start or end tag of an element, which
+ cannot be a child of table element, appears
+ in the input stream while the table element has been opened
+ but no other element has been opened. The document is non-conforming.
In The document does not start with a There is a start tag of the In an HTML document, there cannot be more than one
+ The document contains a table, only table related elements
are allowed; any other element must be contained in
@@ -216,7 +393,7 @@
DOCTYPE.DOCTYPE.
@@ -242,14 +419,32 @@
<html> tag is not
+ the first start tag.html element
+ that it not the first start tag in the input stream.
+ The document is non-conforming.html element and therefore there cannot be
+ more than one <html> tag. In addition,
+ nothing can be placed before the <html> tag
+ except a DOCTYPE, white space characters,
+ and comments.DOCTYPE declaration
- that is different from HTML5 DOCTYPE (i.e. <!DOCTYPE
- HTML>). The document is non-conforming.DOCTYPE (i.e.
+ <!DOCTYPE HTML>). The document is non-conforming.
The document might or might not be conformant to
some version of HTML. However, conformance to any HTML
@@ -263,6 +458,13 @@
class="parse-error">
An end tag appears though no element with the same name
+ has been opened. The document is non-conforming. For any end tag in HTML document, there must be a
+ corresponding start tag.$0 is not
opened.
Possible causes: -
a or span)A data character cannot be a child
- of certain sectioning elements such as body,
- section, and blockquote.
Any inline-level content must be put
- in e.g. paragraph element such as p.
div or hn)Though some elements such as div,
- li, and td allow
- either one of block-level or inline-level content
- is allowed. If there is a block-level content,
- any inline-level content must be put
- in e.g. paragraph element such as p.
A data character cannot be a child
+ of certain sectioning elements such as body,
+ section, and blockquote.
Any inline-level content must be put
+ in e.g. paragraph element such as p.
Though some elements such as div,
+ li, and td allow
+ either one of block-level or inline-level content
+ is allowed. If there is a block-level content,
+ any inline-level content must be put
+ in e.g. paragraph element such as p.
Possible causes: -
a or span)a, progress, or imgAn inline-level element cannot be a child
of certain sectioning elements such as body,
section, and blockquote.
Any inline-level content must be put
in e.g. paragraph element such as p.
div or hn)div, hn, or
+ sectionThough some elements such as div,
li, and td allow
either one of block-level or inline-level content
is allowed. If there is a block-level content,
any inline-level content must be put
in e.g. paragraph element such as p.
html elementnoscript elementnoscript element is allowed only in the context
+ where a block-level or inline-level content is expected
+ and in the head element.
+ It cannot be used in e.g. ul, table,
+ or select.html element
+ that is the root element of an XHTML documentIn an XHTML document, the root There must be an element before another element, but there
+ is not. The document is non-conforming. For example, there must be a The The The To specify natural language information in HTML document,
use XHTML 1.0 Appendix C was encouraged to specify both
+ html
element must have an xmlns attribute
whose value is set to
@@ -372,6 +578,19 @@
+$0
+ element before this element.dt element
+ before any dd element.xml:lang attribute is not allowed in
HTML document. The document is non-conforming.xml:lang attribute in null
- namespace for HTML elements is defined as conforming only for
+ lang attribute in the null
+ namespace for HTML elements is defined as conforming only for
XML document.lang attribute instead.lang and xml:lang attributes with
+ the same value. Such a duplication has no effect in practice.
+ Use only one of lang (in HTML) or xml:lang (in
+ XML).
The lang attribute in null
- namespace for HTML elements is defined as conforming only for
+ namespace for HTML elements is defined as conforming only for
HTML document.
To specify natural language information in XML document,
@@ -468,7 +694,8 @@
The specified link type cannot be used for the element.
+ The document is non-conforming. Link types are associated with limited set of elements.
+ They cannot be used with other elements. For example, link type The specified link type is non-conforming, and therefore
+ the document is non-conforming. The specified browsing context name is reserved.
The document is non-conforming.{@} is not one
+ of them.
$0
+ cannot be specified for this element.bookmark
+ can be used with a or area element,
+ while it cannot be used with link element.$0
+ is non-conforming.
+
+ contentsindex.copyrightlicense.homeindex.startfirst.tocindex.{@} is reserved._blank,
_main, and _replace.
However, they are not conforming attribute values.
$0
+ is proposed but not accepted yet; it should not be
+ used until it has been accepted.The link type is in the proposed status; it + should not be used until it has been + accepted.
+ +Warning: The data served to the + conforming checker might be out of date; it might have already + been accepted or rejected, depending on which the document + might be conforming or non-conforming. See WHATWG Wiki + for the latest information.
+th) in the last row.
+rowspan attribute
+ results in creating a table row that does not contain
+ any cell anchored to it.The rowspan attribute value of the cell
+ is so specified that it extends a table in the row axis.
+ However, the extended row does not contain any cell by itself.
+ The document is non-conforming.
For example, the table below is non-conforming: +
<table>
+<tbody>
+<tr><td rowspan=2></td></tr>
+</tbody>
+</table>{@}: An obsolete
+ subtype is used.x- or x.)
- subtype is used.{@}: A private
+ (x- or x.) subtype is used.{@}: The subtype is
+ not registered to IANA.The specified value does not satisfy the syntactical requirements + for IRI references. The document is non-conforming.
+ +Possible causes: +
(U+0020
+ SPACE) character cannot be
+ used in IRI references./.
+The hexadecimal digit in percent-encoding string in the IRI + is in lowercase. Though the IRI is conforming, + it should be in uppercase.
+An unreserved character is percent-encoded in the IRI. + Though it is conforming, it should be in the + decoded (or bare) form.
+The scheme part of the IRI is written in uppercase letter.
+ +Uppercase scheme names are not required to be processed + correctly.
+ +$0 is not standardized
- or registered at the time of the release of the conformance checker;
- it is non-conforming unless it has now been registered.$0 is not
+ standardized or registered at the time of the release of the conformance
+ checker; it is non-conforming unless it has now been
+ registered.The rel attribute is defined as a list of link types.
Some common link types are defined in the HTML5 specification.
@@ -618,6 +990,38 @@
$0 is not supported;
+ it might or might not be conforming.$0 is not supported;
+ it might or might not be conforming.