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[lang] attributes do not have a valid value

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Appears in: Accessibility audits

To ensure correct pronunciation, screen readers use a different sound library for each language they support. Screen readers can switch between these language libraries easily, but only if a web page specifies which language to read for a given piece of content.

If the language changes within your page, you must specify a valid BCP 47 language to ensure that the section in the new language is pronounced correctly.

How the Lighthouse invalid lang attribute audit fails

Lighthouse flags elements that have a lang attribute with an invalid value:

Lighthouse audit showing elements with an invalid value for the lang attribute

The Lighthouse Accessibility score is a weighted average of all the accessibility audits. See the Lighthouse accessibility scoring post for more information.

How to fix invalid lang attribute values

Use only valid BCP 47 language codes in all lang attribute values.

Resources

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