The extent to which domains impact search engine optimization, and how, has changed over the years. Already rife with misinformation, the topic of domains and SEO continues to confuse and mislead.
First, a little level setting. A “domain” is the piece of a URL that people identify with most strongly — the “yoursite.com” piece. The image below illustrates the different pieces of the domain’s URL in both technical and more commonly used terms.
The domain serves as the friendly address for a site on the web. Each domain is mapped to an IP address, a string of four numbers that serves as the actual server-level address for a site. IP addresses are like GPS coordinates, and domains are like street address that people use to remember a location.
When it comes to domains and SEO, the following five areas can benefit or harm organic search performance.
Exact Match Domains
Once upon a time, exact match domains were one of the best ways to dominate search results. Today, their influence is waning, except when paired with other strongly positive algorithmic signals.
For example, seven years ago if you sold shoe laces and your domain was shoelaces.com, it was a very strong signal that helped you rank on the first page of search results. As a result, businesses snapped up domains with keywords in them, often resulting in ridiculous strings of hyphenated words like shoe-laces-online-store.com.
People started to use these keyword domains to win search rankings for armies of spammy sites that weren’t beneficial to searchers, introducing an unfair advantage in organic search. As often happens with the combination of unfair SEO advantage and poor searcher experience, search engines began diluting the influence of exact match domains on their algorithms.
Recently, algorithm updates like Google’s Exact Match Domain update in 2012 have decreased the individual influence that keyword domains have in relation to other important ranking signals like link authority and content quality.
In other words, having a keyword domain is a benefit if you also have other strong SEO signals like a quality link profile and unique, high-quality content. However, spammy sites that host scraped content with no quality signals shouldn’t be able to rank well based solely on their keyword domains.
There are many examples where sites that shouldn’t are winning based on this unfair advantage. The point is, it’s an advantage that the search engines are actively working to remove. Do not try to use it to your advantage in the short term.
I touched on it above, but let’s talk more about authority and domains. Every site that links to any page on your domain passes some amount of link authority to that page. It’s like a little vote of confidence in the quality of your page’s content. The more votes of quality your individual page gets from other quality sites, the higher opinion search engines have of your individual web page.
Every site that links to any page on your domain passes some amount of link authority to that page. It’s like a little vote of confidence in the quality of your page’s content.
Domains are special when it comes to authority because the domain aggregates the link authority that all of your individual pages earn. Think of it like water droplets on a plant’s leaf. Each leaf collects droplets of water when it rains, and the water serves to nourish the whole plant.
Every page on a subdomain shares its link authority freely with the whole. If the domain hosts different subdomains, each subdomain may share its authority with the other subdomains on that domain. But different domains do not share authority between them, even if the same company owns them.
Hosting an Additional Site
The concept of domain authority is especially important when it comes to hosting a microsite, blog, store, forum, or other type of content related to your primary website. Many marketers get caught up in the excitement of a new web project and immediately rush to buy a new domain.
Stop. Consider the benefits of domain authority to SEO before hosting content on a different domain. The best-case scenario for SEO is to host the new content on a directory of the primary site. This allows the new content to share fully in the domain authority the primary site has already worked so hard to earn.
If a directory isn’t possible, consider a subdomain. Any content, regardless of whether it uses a different platform than your primary site, can be hosted just as easily on a subdomain of your exiting site’s domain as on a separate domain. Content hosted on a subdomain may share the primary site’s domain authority, if the content on the subdomain isn’t too radically different from the primary site’s purpose.
Hosting content on a new domain requires time and dedicated effort to build domain authority from scratch. Until that happens, the only way customers will find the new content is via a link from your site or via some form of marketing effort. Organic search will very rarely drive significant traffic to a new domain.
Buying a Strong Domain
Some try to shortcut the process of building a new site’s domain authority by purchasing an existing domain to benefit from its longer history and inherit its links. It’s unlikely that purchasing a domain would actually accrue historic link authority to the new site.
There is no evidence to indicate the impact of this tactic, largely because no one SEO entity has access to enough data points to be able to draw a conclusive result. However, we can make some assumptions based on history and what we know about the search engines’ behavior and access to data.
Every major search engine in the U.S. is also a domain registrar. That means that the search engines can see who owns a domain, when it changes ownership, when hosting information changes, and many other small signals that indicate a significant change in a domain’s usage. Pair that with an index of every page they’ve ever indexed stretching back to the late 1990s, and it’s just not possible to fool search engines into thinking that a domain you’ve purchased deserves the link authority that another site has earned.
To play devil’s advocate, let’s say there was a positive correlation between a past site’s domain authority and the domain authority of the site that recently purchased the domain. If we make that assumption, it’s just as likely that a domain’s past mistakes could haunt the new site on that same domain as well.
If the seller engaged in purchasing links, article spam, low-quality or scraped content, doorway pages or any number of other black hat SEO tactics, those could just as easily be connected with the new site as any positive SEO attributes like high quality link profiles.
The bottom line is that since we have no hard data, treat this as a risky tactic. If there are other business reasons to purchase a domain and host new content on it, then absolutely consider it. But if SEO domain authority is your primary reason for purchasing the domain, it’s not a sound tactic.
As part of the due diligence in purchasing the domain, investigate its past and present using tools like Archive.org’s Way Back Machine to see cached versions of the site through the years, and link-checking tools like Majestic SEO to scope out any remaining links to the site. If there’s any whiff of spam, I would consider that a strong risk factor in purchasing the domain, especially if other, cleaner domains are in consideration.
Defensive Domain Registration
Sometimes businesses need to register domains simply to ensure that others don’t register them and use them for their own purposes. This is a business necessity, not an SEO-positive tactic.
When a domain is purchased it can be parked at a hosting company, 301 redirected to the primary domain, or used to host content. Parking the domain basically puts it away for safekeeping. It won’t rank in search results, but if someone types the domain directly into the browser they’ll see an advertisement for your hosting company.
You could choose to 301 redirect the unused domains to your primary domain. There won’t really be any SEO value unless someone builds a link to your domain and misspells it, and you happen to have registered that misspelled domain. It’s unlikely — but it could happen. The other benefit is that people who type your defensively registered domains into their browser will be redirected to your primary site instead of seeing an ad for your hosting company. These are all edge cases, but it really doesn’t take much to 301 redirect defensively registered domains instead of just parking them. For the low effort involved, even if the return is low, it’s worth it.
The last option is hosting a copy of your primary site at one or more of these defensively registered domains. Do not do this. Hosting duplicates of the same site at different domains does not give you the opportunity to rank multiple times for the same content. Instead the search engines see it as low-quality duplicate content at best and a spam tactic at worst. In some cases, it could even negatively impact the performance of your primary site.