# lang The `lang` prop on the `` element must have a valid value based on ISO country and language codes. #### References 1. [axe-core, valid-lang](https://dequeuniversity.com/rules/axe/3.2/valid-lang) 2. [ISO Language Codes](http://www.w3schools.com/tags/ref_language_codes.asp) 3. [ISO Country Codes](http://www.w3schools.com/tags/ref_country_codes.asp) ## Rule details This rule takes no arguments. ### Succeed ```jsx ``` ### Fail ```jsx ```