Audit rules

HTML Language Attribute

The <html> element has no lang attribute, or its value is not a valid BCP 47 tag such as en, en-US or zh-Hant-TW. In a QuikSEO audit, a failure has warning severity and counts against the score. The exact condition, its exceptions and its sources follow below.

01 — Definition

How This Rule Is Checked

The rule is a pure function of the fetched page: no extra requests, no account settings. The same input always gives the same result.

Rule Severity and Score

Rule id: document.lang
Group: Document
Severity of a failure: Warning
Counts in the score: Yes, whenever it applies to the page
Required for a score: No
Replaces the check: language

Condition and Exceptions

Condition: <html lang> missing or not a valid BCP 47 tag (language 2-3 letters, optional script/region, e.g. en, en-US, zh-Hant-TW) → fail
Exceptions: —

Sources

Sources: HTML Standard, 3.2.6.2 The lang and xml:lang attributes (WHATWG, Q48)
Understanding Success Criterion 3.1.1: Language of Page | WAI | W3C (W3C, Q89)

02 — Document

Other Rules in This Group

The other checks of the same group, each with its own condition and sources.

Character Encoding Declarationdocument.charset
Deprecated HTML Tagsdocument.deprecated_tags
Doctypedocument.doctype
Favicondocument.favicon
Inline CSSdocument.inline_css
Meta Keywordsdocument.meta_keywords
Meta Refreshdocument.meta_refresh
Meta Viewportdocument.viewport