(Psst. Want to know what domains names are, but feeling a bit shy about asking? Here's a great article about domain names on Moz.com)
You're probably hoping that if you buy the domain name version of the keyword you want to rank for, Google will help you rank better for that term. It probably won't help. Let's dive in a bit.
What's the Whole Multiple Domain Buying Scenario
Let's say you are an internet marketing agency in Baltimore (just a hypothetical ;), and your website address is AbilitySEO.com (again, just a hypothetical ;). You'd like to be #1 on Google when someone searches for "internet marketing agency Baltimore". So, you might go and buy the domain name InternetMarketingAgencyBaltimore.com and do the tech-work so that whenever someone types in "InternetMarketingAgencyBaltimore.com", she'll be taken to your website: "AbilitySEO.com". Will this help your SEO?
Buying Additional Domain Names Will Not Help Your Google Rank
Kinda, sorta, absolutely not. Here's why: $551,410,000,000 <--- the approximate market value of Google's parent company Alphabet Inc. as of 5 Jan 2016 (source). Google is really smart. That's why we "google" things all day long (@ 60,000 searches / second). What comes up on top is what Google thinks we're most likely to want.
Now ask yourself, does owning another domain name make your more likely to be what people want? Probably not. Does Google, the $551 billion gorilla in the room, think that people buy domain names in order to rank higher? Yup. Does Google agree with you that owning multiple domain names will not make you a better match for someone's search? I'm going to say yes.
But Domain Names are Only $11!
I know. It's fun. I do it too. You can even get them for like $0.88. (namecheap.com)*. Think of it as a fun way to daydream about building a new business, new brand or new blog. Just don't think of it as a way to improve your SEO.
Good discussion on Moz about this topic here:
*Full disclosure. This is an affiliate link, and I will get some kickback from the $0.88 you spend on more domains. I'll try not to spend it all in one place.
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