Why does Moz recommend subdomains for language-specific websites?

[AdamThompson]

In Moz's domain recommendations, they recommend subdirectories instead of subdomains (which agrees with my experience), but make an exception for language-specific websites:

Since search engines keep different metrics for domains than they do subdomains, it is recommended that webmasters place link-worthy content like blogs in subfolders rather than subdomains. (i.e. www.example.com/blog/ rather than blog.example.com) The notable exceptions to this are language-specific websites. (i.e., en.example.com for the English version of the website).

Why are language-specific websites excepted from this advice? Why are subdomains preferable for language-specific websites? Google's advice says subdirectories are fine for language-specific websites, and GSC allows geographic settings at the subdirectory level (which may or may not even be needed, since language-specific sites may not be geographic-specific), so I'm unsure why Moz would suggest using subdirectories in this case.

[AdamThompson]

Thanks, I'll send you a PM.

[katemorris]

Ah, I think we are getting to the root of the problem here.

If we are talking about hreflang used correctly between two identical pages that are translated, everything Google has stated about hreflang is that it acts as a canonical. The alternate language pages would be treated as changes of each other. Ranking is more than just link equity though, so where you rank is more than that.

In your specific situation, I see a few problems outside the use of hreflang. Can you share the domain you are talking about? If you're not comfortable sharing it here, please message me with it. There might be other things at play confusing the Google algorithm. But I need to see for sure.

After spending the last five years looking into international expansion of websites, I can say for sure I don't recommend subdomains for language translations. It's due to the fact that using subdomains isn't very clean and doesn't work well if you want to expand to country specific content in the future.

The way I read the original Moz post on subdomains is that the use of hreflang helps some of the assumed negatives of using subdomains, but subdomains are not the recommended solution. Mind you, the "negatives" of subdomains have not been proven in all cases either.

Let me know about your specific case and I'll see what might be happening.

[AdamThompson]

OK, that's very good to know. I missed that.

Here is the Google source I found that implied that hreflang tags do not combine/consolidate link metrics:

"Generally speaking, the rel-alternate-hreflang construct does not change the ranking of your pages. However, when a page where you use this markup shows up in the search results, we may use this markup to find alternate, equivalent pages of yours. If one of those alternates is a better match for the user, their query language, and the location, then we may swap out the URL. So in practice, it won't change the ranking of your pages, but it will attempt to make sure that the best-suited URL (out of the list of alternates) is shown there." ~John Mueller

This seems to be describing a "swap out" effect rather than a consolidation of metrics. In my mind, that sounds different. It sounds like what John is saying is that "if your main site ranks for the keyword "barcelona" in English search results, if someone searches in Spanish we'll give you the same ranking, we'll just display your Spanish URL instead". That seems different from a consolidation to me (the Spanish URL isn't being given the link authority from the main URL to help it rank for other Spanish keywords, it's just being swapped out in SERPs where the English URL already ranks). Of course Google hasn't released the details so I'm guessing a bit here.

"Gianaluca was speaking of multiple "sites" but this is translation."

My issues is where multiple sites and translations are the same thing, i.e. when you have different language versions of your site on different subdomains. Gianaluca seems to be saying that hreflang will not consolidate link authority across your sites that are in different languages. Here's another source saying the same thing: https://www.semrush.com/blog/7-common-hreflang-mistakes-and-how-to-fix-them/

I've got a situation now where it appears that Google is not consolidating/sharing link signals efficiently between the language versions that are hosted on separate subdomains. My concern is that part of the issue may be the fact that the different lanaguage versions are on different subdomains. That's why I'm keen to know why Moz excepts language-specific websites from their "no subdomains" advice.

Any thoughts?

[katemorris]

Gianaluca was speaking of multiple "sites" but this is translation. Google does say it in fact:

"By specifying these alternate URLs, our goal is to be able to consolidate signals for these pages, and to serve the appropriate URL to users in search. "

https://googlewebmastercentral.blogspot.com/2011/12/new-markup-for-multilingual-content.html

[AdamThompson]

"use hreflang and that acts like a canonical"

Google and other sources don't indicate that hreflang will pass/consolidate link authority. So I think hreflang and canonical tags are different in that regard. Based on that and what I've seen, I don't see that hreflang tag would negate the disadvantages of a subdomain. If you have evidence it does, though, I am very interested!

[katemorris]

I actually disagree with the subdomain exception for languages. You can use a subdomain for languages, but it doesn't look right in my opinion. The reason that text is in there though is because if you use translated content (which is different from regional or country targeted content), you should use hreflang and that acts like a canonical. The possible downsides of a subdomain are negated with that tagging.

The writer of this text you are referencing is not saying subdomains are preferred, merely that with languages the downsides of a subdomain are not applicable.

[Mobilio]

Well - IMHO we are too deep in technology and know differences between multi-regional and multi-lingual sites. But when talking to someone "newbie" he easy can be confused with ton of terms. That's why they give example with something easy to be understanding.

[AdamThompson]

"But you can't change server location with subdirectories. With subdomain you can make de.example.com and place this in German server and es.example.com and place this in Spanish server."

What you're talking about is geographic targeting, but Moz was specifically referring to language-targeting. Those are similar, but they are subtly different things.

Language-specific sites are not necessarily targeted to a specific country. They can target multiple countries (eg Spanish speakers in US, Spain, Mexico, etc.) or you might have two Language-specific sites targeting the same country (eg an English and a Spanish site both for the US).

So if a language-specific site isn't a geographic-targeted site, I still don't understand why Moz would recommend a subdomain in that case.

[donford]

Great Answer Peter!

/thumbs

Don

[Mobilio]

Well there are 4 types of multi-lingual or multi-regional sites that are described here:
https://support.google.com/webmasters/answer/182192?hl=en
Summary - best is ccTLD, next is subdomain with gTLDS. On 3rd is subdirectory with gTLDS and URL parameters is last.

So Moz is trying to diving expert advise to webmasters to NOT use subdomains and giving famous blog example. I fall in this trap almost 15 years ago with subdomain. I wish someone to told me about this then... Other examples can be catalog and different products (catalog.example.com vs. example.com/catalog; product.example.com vs. example.com/product/). This advice in same subdomain keep link juice inside, but you probably know this.

GSC allow setting different directories to specific geo-location. That's true. But you can't change server location with subdirectories. With subdomain this is possible. Example - one company with site of Spanish and German. With subdirectory i have one server and /de and /es folders. But in this case server location is one and only. And server IP is some of signals for geo-targeting so you have tough choice where to be. With subdomain you can make de.example.com and place this in German server and es.example.com and place this in Spanish server.

That's why subdomains for multilingual sites is notable exception of golden rule "do not use subdomains".