Subdomains vs. Subfolders: Does Google Rank Them Differently?

When you’re mapping out your website’s content structure, should your content be stored under a subdomain or subfolder? Will your choice influence how Google decides to rank your content?

For years, website owners and SEO professionals have been paying close attention to how content structure influences search engine ranking.

If your site content doesn’t have a logical structure, visitors can quickly become confused over the topics that your website covering and how they can efficiently navigate towards finding their desired content.

Crafting an impeccable user experience comes with a lot of considerations, including whether you wish to store particular content under a subdomain or subfolder.

In this article, we will explore:

• The debate surrounding subdomains and subfolders.
• The history of Google’s comments on the matter.
• The opinions of SEO professionals on the debate.

Many website owners choose to distinguish content from the rest of their site using a subdomain. For instance, this can be done when certain content is different from what is on their main website. This is something that we see quite a lot when there is a blog.mysite.com counterpart.

The diagram below sheds some light on how the underlying structures of each site differ when organized into subdomains and subfolders.

What is the main difference between a subdomain and a subfolder?

This part is easy. All you need to do is understand the anatomy of a URL.

Let’s take this URL as an example: subdomain.reputio.com/subdirectory/

In this example, the subdomain is the subdomain and the subfolder is the subfolder (also known as subdirectory as per the diagram above).

The most common use for a subdomain is to organize and divide web content into distinct sections, or niches. If a website has a significant amount of content on multiple topics, a subdomain can give each of these sections a unique web address without having to register a new domain name.

A good example is Google. Google has a different subdomain for each of their services: www.google.com, images.google.com, news.google.com, mail.google.com, etc. Typically, the subdomain will consist of a keyword that is relevant to the subdomain’s content.

Subfolders on the main domain create a straight-forward and simple site structure that can be easily crawled by search engines like Google. This phenomenon, many have argued, may make pages within subfolders rank higher than pages on subdomains.

Similarly, backlinks from pages in subfolders may be valued more than backlinks in pages from subdomains – but that’s a debate for another day.

In recent years, a number of questions have been raised about subdomains and subfolders:

• Does Google treat these two site structures in different ways?
• Will Google crawl, contextualize and rate the two site structures differently?
• Can the authority of a root domain carry through into subdomains?

Before we jump to any conclusions on the impact of subdomains and subfolders on your websites, let’s hear what Google has said about the debate in recent years.

What does Google say about the debate?

To determine whether Google prefers a certain type of link structure, we need to understand if Google sees a difference in their ability to provide audiences with value.

It’s important to remember that Google is ultimately the decision-maker when it comes to the value of these link structures. You can think of them as the gatekeeper that focuses on quality control.

Do subdomains spread your traffic too thin?

If you have a website’s content under one single domain, using subfolders rather than subdomains, this has the potential to strengthen the authority of your primary domain.

It could also be suggested that webmasters who choose to use subdomains over subfolders run the risk of spreading their traffic too thin, across multiple domains.

How does Google crawl subdomains?

When Google is crawling a website, if it encounters multiple subdomains, it will treat them as separate domains. With traffic spread across multiple domains, this has the potential to affect SEO.

Alternatively, with subfolders, all content that attracts traffic will contribute towards the main domain’s overall authority.

Could subfolders be easier for Google Analytics to track?

Many webmasters prefer subfolders over subdomains for tracking purposes. Staying across multiple domains and tracking their data on a platform like Google Analytics can quickly get confusing. Keeping everything under one roof with subfolders enables webmasters to compile consolidated data.

In comparison with subdomains, the use of subfolders prevents webmasters from having multiple domains competing with each other. It’s every webmaster’s worst nightmare when it comes to search engine optimization.

Google’s John Mueller shares his thoughts

A few years ago during an office-hours hangout, John Mueller, a Google Webmaster Trends Analyst, weighed in on the debate. On the call, Mueller was asked whether Google treats subdomains differently to subfolders.

In a rather anti-climatic response, Mueller confirmed these two structures were generally treated equally by Google’s search engine.

It was a reasonably brief and straightforward answer from Mueller, offering only a short explanation on Google’s position in relation to the debate.

“In general, we see these the same. I would personally try to keep things together as much as possible. So, if it’s the same site then try to put them on the same site, essentially, and use subdomains where things are really kind of slightly different,” Mueller explained.

He continued, “There are lots of really strong opinions on this so, from my point of view, this is something that could go either way. If you have really strong reasons to go one way or the other then, obviously, that might be what you’d want to watch out for. On the other hand, if you’re like ‘well I don’t care either way’ then I would just keep it within the same site.”

Google’s Matt Cutts weighs in

Several years ago, Matt Cutts, a software engineer who previously worked with Google as part of the search quality team on SEO issues, shared his thoughts on the debate.

Speaking on his own personal preferences, Cutts likes the convenience of subfolders for most of his content. “A subdomain can be useful to separate out content that is completely different,” Cutts said. He also mentioned the example of how Google uses subdomains to distinct and unique products, such as news.google.com and maps.google.com.

Do SEO Professionals agree with Google?

SEO professionals have often found themselves at odds with Google’s decision-making. Whilst Google’s leading engineers and analysts have briefly shared their thoughts on subdomains and subfolders, do SEO professionals agree with Google’s agnostic view?

Rank Fishkin from SparkToro

Speaking in a recent interview, Rand Fishkin, founder of SparkToro, shared his thoughts on the debate: “It’s damn hard to argue that there’s ‘no difference’. Content that’s placed in a subfolder will almost always perform better in Google than the same content placed in a subdomain”.

Fishkin also feels that subfolders can be easier for website visitors to navigate through: “They make for cleaner web URLs that are easier for most people to visually parse – and processing fluency is correlated with more sharing, more clicking, more of all the things website owners want”.

Sam Silverwood-Cope from PI-Datametrics

Sam Silverwood Cope recently spoke about the idea of subdomain cannabilisation in one of his recent articles. In the article, he said: “As we’ve seen, Google used to offer up separate results for separate subdomains, so that multiple subdomains would feature in the SERPs. However, since this practice was ultimately being abused, Google now ‘scrunches’ those results together. This is a good example of everyone suffering from the practices of the very few”.

In other words, Google’s algorithm could potentially think that your subdomain is some sort of third-party platform and therefore shouldn’t get the same authority as the root domain.

Stephen Kenwright from Branded3

Stephen Kenwright from Branded3 also shared his thoughts on the use of subdomains and subfolders. He stated that he almost always prefers subfolders over subdomains, except when the creation of subfolders isn’t possible for technical reasons.

“I’ve worked with several brands who have experienced an increase in organic traffic when migrating from international subdomains to international subfolders – this usually occurs when there’s a lot of link equity in one or two countries and less-favored international sites are underperforming,” Kenwright explained.

Conclusion

In the SEO community, there seems to be strong agreement on the idea that subfolders are preferable over subdomains for the following reasons:

• Subdomains may not always show up in the SERPs, as Google “scrunches” these results together, only giving authority or your root domain. In other words, you could end up with multiple domains competing with each other.

• Subfolders will be able to pick up more “link equity” from your root domain than subdomains. This means that subdomains are likely to have less authority than your root domain.

• Subfolders can be easier for visitors to navigate through, making for cleaner URLs.

If you are currently debating over whether to use a subdomain or a subfolder, the common consensus, outside of Google, is that you should try to use subfolders where possible. By doing this, you can ensure that the SEO authority of your root domain is carried through into your content and that you won’t have multiple domains competing with each other in SERPs.

Do you require advice on subdomains and subfolders? Please contact us to schedule a free SEO consultation