How important is it to have a .com domain name?

Everyone has an opinion, but as far as I know there’s never been a good study comparing domain extensions’ performance.

Until now.

We ran an experiment with 1,500 people to find out how they would react to eight popular domain extensions (top-level domains): .com, .net, .org, .co, .biz, .us, .blog, and .io.

Summary of key findings

  • .com domains are over 33% more memorable than URLs with other top-level domains.
  • .com is the #1 most trusted TLD, with .co in a close second place.
  • When people misremember a URL, they’re 3.8 times more likely to assume it ends in .com than anything else.

Read on for the rest of the results and see how the other TLDs performed — you might be surprised.

Or click here to get the upgraded PDF version of the full results, including a few bonus demographic-specific takeaways that aren’t in this article.

Method: Who we studied and how

We conducted this research using a tricky survey structure with three major parts:

Part 1: Perceived trustworthiness. We asked how trustworthy people would expect a site to be based purely on its URL, using the made-up brand “mattressrankings.__” as the domain, with the blank filled in randomly with either .com, .net, .org, or one of the five other domain extensions I mentioned above. (We did not specifically draw people’s attention to the domain extensions.)

As you can see, those domain names are currently available for between $12 – $30 per year, with the exception of the .com version which costs an extra $4,250:

Domain registration prices for different domain extensions

(Clearly someone believes the .com version is a lot more valuable.)

Part 2: Palate cleanser. The second part of the survey consisted of several unrelated questions designed to distract people and find out their demographics.

Part 3: Memorability. Now that they’d been distracted for a little while, in the last part of the survey we asked people to write the exact URL they saw at the beginning. (They were not able to go back to the original question to see it again.)

Here were the demographics of the 1,500 people surveyed:

Respondent locations and ages

(In retrospect, we should have used different age brackets since so many people ended up in the 26 – 40 range.)

How much do people trust different domain extensions?

Trustworthiness is extremely important.

A URL that is perceived as being trustworthy is more likely to get clicked on, linked to and shared. And it’s easier to build a brand on top of.

Here’s how the top-level domains fared in terms of perceived trustworthiness, on a scale of 1 – 5:

Domain extensions perceived trustworthiness

As you can see, .com comes out on top with a score of 3.5. But it doesn’t win by a huge amount: .co comes in right behind it with a 3.4, followed by .org and .us with 3.3.

Bringing up the rear is .biz with a 2.9 trust rating: 17% lower than .com’s. And .io doesn’t do much better than that.
Key takeaway: .com is the #1 most trusted domain extension, with .co in a close second place.

How memorable are different domain extensions?

An important factor for any URL is how easy it is to remember.

The question we wanted to answer is, are people more likely to remember URLs with some TLDs over others?

As you can see, yes they are:

Domain extensions memorability rankings

The .com domain extension comes out on top here again, with a 44% memorability score. (Meaning people correctly remembered the .com URL 44% of the time.)

And .co again comes next, but this time it’s a more distant second place: at 33%, it’s a full quarter less memorable than .com.

Comparing .com to its two traditional main competitors, .net and .org, you can see it’s not even close.

Interestingly, .biz actually does better than .us, .io, .net, and especially .blog (which is the least memorable).

I was also surprised to see .net perform so much worse on this test than .org.

Here are those same memorability results alongside the trust ratings we saw before:

TLD trust ratings and memorability

So far .com is winning this race, with .co in second place overall and .org in third.
Key takeaway: .com URLs are over 33% more memorable than URLs with other TLDs.

When people remember the top-level domain incorrectly, which TLD do they say instead?

This last factor is an interesting one: when people remembered the URL almost correctly — when they got the “mattressrankings” part right but put the wrong domain extension after that — which domain extension did they say?

This helps us see how much of a bias people have in favor of each TLD.

For example, if the correct URL was mattressrankings dot net but they misremembered it as mattressrankings dot com instead, that would be a “point” for the .com TLD.

Here’s the data:

Domain extensions times used instead of actual - bias toward .com

First place again goes to .com, by far.

Out of all the wrong-but-almost-right answers, 57 of them said .com instead of the correct TLD. That’s 3.8 times more often than the next highest, .org.

This is strong evidence that .com domains are still thought of as the default.

When people aren’t sure which TLD a URL uses, they’re much more likely to guess .com than anything else.

The distant second place goes to .org, which people guessed only 15 times: 26% as often as they guessed .com.

Not shown on the chart above is the .co.uk domain suffix, which received two guesses but wasn’t a subject of this study (maybe I’ll do another study to cover more country code top-level domains / ccTLDs).
Key takeaway: People are 3.8 times more likely to assume a URL ends in .com than in anything else.

Final results: Full comparison of all eight domain extensions, plus expert opinions

Here are all three ratings for the list of domain extensions in a single chart:

TLD trust ratings, memorability and times used instead of actual

If you’re considering .com vs .org vs .net, according to this data .com seems to have a sizeable edge.

A closer contender in most regards would be .co, but .com still comes out on top:

  • .com URLs are over 33% more memorable than URLs with other top-level domains.
  • .com is the #1 most trusted TLD, with .co in a close second place.
  • When people misremember a URL, they’re 3.8 times more likely to assume it ends in .com than anything else.

Back to the domain registration pricing I shared at the beginning of this article: is mattressrankings.com really worth $4,250 more than the same URL with another domain extension?

For a business, to me it seems like a clear “yes”; the benefits shown above would almost certainly be worth more in the long-term than a one-time payment of ~$4K.

However, as Cyrus Shepard points out below, that doesn’t mean .com is always the best choice. Non-profits aren’t required to use the .org TLD, but don’t wikipedia.com, savethechildren.com, and charitywater.com all look pretty strange compared to their .org alternatives?

Let’s see what else Cyrus and a few other experts have to say about these findings.

Cyrus Shepard, Founder of Zyppy.com:

“Wow, terrific study. A few things jump out at me.

1. Obviously, this reinforces .com as the standard choice of domain extensions. As the old saying went, ‘Nobody ever got fired for buying IBM’ (computers). Similarly, buying the .com if you can get it, is typically going to be your best bet. (unless, of course, a visible brand is using one of the other extensions)

2. It’s hilarious to me that people trust .co – a country code top-level domain for Colombia – more than they do .org – a generic top-level domain used by Wikipedia, non-profits, and other orgs.

3. I’d stay away from .biz domains at all cost. Not only does this survey show a low trust, I’ve seen several other studies over the years that show folks tend to associate this extension with spam.

4. Finally, despite the dominant trust and memorability of .com domains, I believe it’s still fair to use the extension that best works for you. Most of the time, that’s going to be the .com. Many sites—Wikipedia being the obvious example—use .org and other extensions with little actual downside. Of course, if you’re a smaller player, or there are other businesses with similar domain names in your space, it’s always going to be best to go with the .com, the reasons for which are made obvious by this survey.”

Glen Allsopp, Founder of Gaps and Detailed

“I had to double check the .biz numbers with Kyle as I just couldn’t believe them upfront. Nine people, who weren’t originally shown a .biz domain, thought that’s what they might have seen when asked later on? That’s really surprising.

He reminded me that only 9 of 1,500 people acted in this way but I was still shocked.

I’m really happy to see .co domains ranking highly as I naturally trust them more as well. I can’t logically tell you why (close to .com? the new thing for makers?) but it’s nice to see I’m not alone.”

Britney Muller, Founder of Pryde Marketing and Senior SEO Scientist at Moz

“It’s always been industry standard to secure a .com instead of another TLD due to it being so commonly used. The thought process being; people might forget your URL, or go to the .com site if you use a less common TLD. However, we’ve never had any research backing this theory up, UNTIL NOW!

The fact that 57 people used .com instead of the actual TLD is proof of this concept. What surprised me most is that individuals found both .com and .co to be more trustworthy than .org, (which has historically been thought of as being perceived slightly more credible). I’m curious if the equivalent .org and .us perception of trust has anything to do with 19.4% of testers living in Asia and 9% in Europe where .us might be more readily used or hold more weight?

Incredible work, Kyle! We need more studies done like this in our space!”

[NOTE: Britney’s theory is correct: people in the USA rate .org slightly higher than .us (3.27 vs 3.23), while it’s the opposite for people outside the USA (3.42 vs 3.54). – Kyle]

Tim Soulo, CMO & Product Advisor at Ahrefs

“I’m quite surprised with the ‘trust rating’ results. I thought that ‘.com’ would outperform others by a much larger margin.”


What did you think of this experiment? Did the results surprise you?

Leave a comment below to let me know.

And for a few bonus demographic-specific takeaways that aren’t in this article, just click here and I’ll send you the upgraded PDF version.