Any research showing which is easier for humans? SUB.Domain.com or Domain.com/SUB

Question

This may be splitting hairs. But I'm trying to provide a url in an ad.

Two choices are:

Prize.Domain.com or Domain.com/prize

I could also, I guess use www.Domain.com/prize

Answer 1

Personally domain.com/campaign is easier on the eyes, it also sets focus on the company or whoever it is that owns the campaign.

From an SEO point of view there are also advantages to doing it that way (from https://moz.com/learn/seo/domain)

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.

Also, it could be a little easier for the user to navigate to the rest of the site through a url like that since just deleting the /campaign feels more natural than editing the actual domain name.

Answer 2

I know of no research (I'd also be interested if it exists).

For the case you suggest, where you are simply creating a single page as the landing page for your advert, but that is otherwise an extension of your existing site, I agree with @Winter that you should probably put it at https://example.com/prize.

When to use separate domains

As regards the broader question in your title of subdomains vs paths in general, I don't think it's so easy to answer. There may be no research because the answer varies hugely depending on the situation.

It's more of an architectural choice, which depends very much on the shape of the system, and that this choice then impacts on the rest of your UX design.

The name "domain" (and "subdomain") is a very good description of how humans see and use domains vs paths. When you make something its own domain, it helps it to be considered a different conceptual domain in all senses.

Two case studies

I think StackExchange are a good example of how to use subdomains effectively. They had this choice - we could be on stackexchange.com/ux right now. But I think they made exactly the right call in making the UX topic its own subdomain, because they want each of their topic forums to have its own community. And I think that choice has determined how StackExchange is used.

In contrast to StackExchange is Reddit. They also have a website split into communities (subreddits), but these live at sub-paths of the main domain - e.g.: https://www.reddit.com/r/usability/

Even though subreddits can have their own look and feel, this architectural choice to reject subdomains has meant that the boundaries between subreddits are much less clear than between StackExchange communities. This allows them to do certain things more easily, like have a homepage that pulls together posts from many subreddits, but it also means that subreddits feel like less significant communities in their own right.

I am not making a judgement between whether Reddit's or StackExchange's experience is better, but I do think StackExchange's is cleaner.

Separating experiential domains

So when you make something a domain, it will be much more its own thing. And this means both that it has more freedom to be different from the original, and also that it will be harder to integrate it with the original.

I think this decision should then impact significantly on your design and UX decisions. (Sub)domains should have their own distinct branding (although they may only be subtly different) and should be mostly self-contained with only minimal links off to other domains.