# lang The `lang` prop on the `` element must be a valid IETF's BCP 47 language tag. #### References 1. [axe-core, valid-lang](https://dequeuniversity.com/rules/axe/3.2/valid-lang) 2. [Language tags in HTML and XML](https://www.w3.org/International/articles/language-tags/) 3. [IANA Language Subtag Registry](https://www.iana.org/assignments/language-subtag-registry/language-subtag-registry) ## Rule details This rule takes no arguments. ### Succeed ```jsx ``` ### Fail ```jsx ```