WCAG 3.1.1: Language of Page
WCAG 3.1.1 Language of Page is a level A success criterion from WCAG 2.0. The default language of each page is set in the markup, usually with the lang attribute on the html element.
Screen readers choose pronunciation from that attribute. The wrong language makes the page hard to understand.
How to test
View source and confirm html has lang set to the page language, such as en or de.
How to fix
Set the lang attribute to the real language of the page.
Example that fails
The html tag has no lang attribute.
Example that passes the check
The page uses <html lang="en">.
Shopify
Confirm theme.liquid includes the lang attribute from the shop locale.
WooCommerce
Keep language_attributes() on the html tag and set the site language.
WordPress
Set Settings, General, Language, and keep language_attributes() in the header.
Wix
Set the site language in settings so the lang attribute is written.