Ensure every HTML document has a lang attribute
This rule checks that an HTML page has a non-empty `lang` attribute.
Autoren: Jey Nandakumar
Vorherige Autoren: Annika Nietzio
Finanzierung: WAI-Tools
This rule applies to any document element if it is an html element for which all the following are true:
text/html.Note: html elements within iframe and object elements are not applicable as iframe and object elements create nested browsing contexts. However, as these elements are meant to provide a layer of isolation, the declared language of their parent browsing context will likely not be inherited, making it possible for empty lang attributes in nested browsing contexts to also cause accessibility issues.
Each test target has a lang attribute value that is neither empty ("") nor only ASCII whitespace.
The language of the page can be set by other methods than the lang attribute, for example using HTTP headers or the meta element. These methods are not supported by all assistive technologies. This rule assumes that these other methods are insufficient to satisfying Success Criterion 3.1.1: Language of Page.
There are no accessibility support issues known.
lang and xml:lang attributesThis html element has a lang attribute with a non-empty ("") value.
<html lang="en">
<body>
The quick brown fox jumps over the lazy dog.
</body>
</html>
This html element does not have a lang attribute.
<html>
<body>
The quick brown fox jumps over the lazy dog.
</body>
</html>
This html element has a lang attribute with an empty ("") value.
<html lang="">
<body>
The quick brown fox jumps over the lazy dog.
</body>
</html>
This html element has a lang attribute whose value is only ASCII whitespace.
<html lang=" ">
<body>
The quick brown fox jumps over the lazy dog.
</body>
</html>
This html element has no lang attribute, only a xml:lang attribute.
<html xml:lang="en">
<body>
The quick brown fox jumps over the lazy dog.
</body>
</html>
This rule does not apply to an svg element.
<svg xmlns="http://www.w3.org/2000/svg" lang="en">
<text>
The quick brown fox jumps over the lazy dog.
</text>
</svg>
This rule does not apply to a math element.
<math lang="en">
The quick brown fox jumps over the lazy dog.
</math>