Lang attribute makes sure that screen readers automatically use the correct speech libraries for accent and pronunciation.
When listening, correct pronunciation helps understanding. For users of assistive technologies such as screen readers it is particularly important, as some have different speech synthesizers for different languages. For example, “chat” means something different when using English pronunciation rather than French.

Lang Bookmarklet for Accessibility Testing

The lang attribute bookmarklet will identify if there is lang attribute set to the page and language of parts.
Note: the language of parts needs to be provided with a lang attribute for the bookmarklet to show the attribute. Developers manually need to verify if the lang attribute provided for the page and language of parts are correct.

Lang Bookmarklet Code

See the Pen Untitled by HolisticA11Y (@HolisticA11YHub) on CodePen.

We hope these accessibility bookmarklets come in handy during your next accessibility audit.

Reference: Accessibility Bookmarklets