Catalog · Markup · Notice

Invalid lang attribute

<html lang> is missing or not a valid BCP-47 tag. Search engines and screen readers cannot determine the page language.

Check ID INVALID_LANG · Category Markup · Available on every plan

Sec. CD.01 · Detail ◊What, why, how reference content · updated continuously

How to fix it

Set a valid lang attribute on the <html> element (for example, lang="en" or lang="en-US").

Sec. CD.02 · Related ◊Sibling checks in this category 1 related

Wrendex catches invalid lang attribute on every audit. No credit card · All 170+ checks · Full PDF report