Wrong language codes in the hreflang attribute do not get picked up by Google.
Luckily, incorrect hreflang language codes can be corrected with a few steps.
Search engines expect the region code in the Hreflang attribute to be in ISO 639-1 format. If you use the wrong language code, it will not get picked up by Google.
Here’s an example of the ISO 639-1 format:
<a target="_blank" href="https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes'">https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes</a>
The solution is simple: update the invalid language codes to the correct format. Now, you can update language codes manually, but you may need to loop in the dev team.
Another way to update language is to leverage ClarityAutomate, an SEO execution platform, to update your language codes at scale.
This allows you to implement the fix with a few clicks, and resolve the issue in a matter of minutes — not days or weeks.
You can use ClarityAutomate to update all applicable canonical tags across your entire site.
Here’s what the update looks like — notice the change from “eng-us” to “en-us”.