Specify Lang Attribute

ID

html.lang_attribute

Severity

low

Remediation Complexity

low

Remediation Risk

low

Remediation Effort

low

Resource

Reliability

Language

Html

Tags

accessibility, reliability

Description

Flags the root <html> element when it has no lang (nor xml:lang) attribute, or when that attribute is present but blank.

Rationale

Declaring the document’s primary language lets screen readers pick the correct voice and pronunciation, lets spell-checkers and translation tools choose the right dictionary, and lets the browser apply language-specific typographic rules. A page with no lang leaves all of that to a guess, degrading accessibility and internationalisation.

<html>                <!-- FLAW — no lang attribute -->
  <head><title>Hi</title></head>
  <body>...</body>
</html>

<html lang="en">      <!-- OK — language declared -->
  <head><title>Hi</title></head>
  <body>...</body>
</html>

Remediation

Add a lang attribute to the <html> element with a valid BCP 47 language tag, e.g. <html lang="en"> or <html lang="es-ES">.

References