Do you use the country or country and language for subdomains?

Question

We need to do translated pages where we have multiple countries that will be using the same language. The URLs will be based on the Subdomain option or Subdomains with gTLD.

What is the correct subdomain pattern when you have multiple countries using the same language?

Example:

• Language = en --> domain = www.example.com
• Language = en-GB (United Kingdom) --> domain = en-gb.example.com (Is this correct?)
• Language = en-AU (Australia) --> domain = en-au.example.com (Is this correct?)
• Language = en-CA (Canada) --> domain = en-ca.example.com (Is this correct?)

We know that en.example.com is valid, but not sure about en-au.example.com. We are using these language codes. We want to be sure that the different Search Engines such as Google's can determine what the proper language and country is per subdomain.

Answer 1

Google determines language by running your page through a machine learning algo, they don't use tags:

Google uses the visible content of your page to determine its language. We don’t use any code-level language information such as lang attributes, or the URL. You can help Google determine the language correctly by using a single language for content and navigation on each page, and by avoiding side-by-side translations.

Managing multi-regional and multilingual sites - Google

That being said, be sure to use the lang attribute on your HTML to declare the language of your page for less advanced crawlers.

As far as proper subdomain is concerned, crawlers will do just fine with most URL schemes, so it's advised to just do your URLs the most human-readable way. I see no problem with the examples you provided!

Answer 2

The website should use all necessary regional and language variations. It is also recommended to use the same method for setting up language and region-specific pages: either by using HTML tags or via XML Sitemap or HTTP headers. However, this applies to the HTML settings, not to the name of the subdomain. Use any kind of subdomain, the one the you like most.