Link building

A comparison of domain authority checkers for link building


Should Domain Authority Checkers Be Part of Your SEO Toolbox?

A few years ago I wrote about Moz’s domain authority and the fact that it does not represent Google PageRank.

No third-party metrics do.

We still love metrics, however, because they give us a quick method of determining how good a site is for our purposes (which is almost always link building, to me).

It is important to remember that domain authority must be considered in conjunction with many other measures.

What are the main metrics we use to measure domain authority?

Ahrefs domain evaluation

According to Ahrefs:


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“Domain Rating (DR) shows the strength of a website’s backlink profile compared to others in our database on a 100 point scale.”

DR is a relative term that takes into account the number of sites that refer you as well as the number of other domains those sites refer to.

The higher the DR, the more link equity will be transferred to the domains the site is linked to. This fairness is split evenly, so a site that only links to 50 domains may have a greater influence on the DR of its target domains than a site that refers to 500,000 domains.

Semrush Authority Score

Semrush Authority Score

This is the latest entry in the domain authority metrics war.


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According to Semrush:

“The authority score is the result of calculations performed by a neural network algorithm that uses machine learning to measure the authority of each domain based on quality, popularity and backlink signals. “

The authority score measures the overall quality and SEO performance.

It takes into account factors like the number of referring domains pointing to a site, the number of outbound links from each referring domain, follow vs nofollow links pointing to the site, etc.

Moz domain authority

Moz domain authority

It is commonly and by mistake considered to be the way in which Google is authoritative on a website.

According to Moz:

“Domain Authority (DA) is a search engine ranking score developed by Moz that predicts the likelihood that a website will rank on Search Engine Results Pages (SERPs). A domain authority score ranges from one to 100, with higher scores corresponding to greater ranking ability.

Majestic flow of trust

Majestic TrustFlow is a little different from the rest.

Majestic flow of trust

Majestic says:

“Trust Flow, a registered trademark of Majestic, is a quality-based score, on a scale of 0 to 100. Majestic has gathered many trusted seed sites based on a manual web review. This process forms the basis of Majestic Trust Flow. Sites that are closely related to a trusted seed site may see higher scores, while sites that may have questionable links would see a much lower score.


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TrustFlow can also be broken down further than its single main number into topics which each have their own TrustFlow.

This measures how close your site is to the most trusted websites in specific categories like shopping, arts, business, entertainment, etc.

Comparison of domain authority checkers

For the purposes of this experiment, we will use well-known and lesser-known sites.

A comparison of domain authority checkers for link building

As you can see, the top five sites have metrics that all seem to match up pretty well. There aren’t any exceptionally low ones that stand out.


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I imagine readers will recognize these sites as well. I think we would probably all agree that they are authoritative and that a connection on their part would be great.

The Punk News site is the one I chose because for me it is the most authoritative site on punk rock. It also has consistent measures at all levels.

However, getting a link to your campsite probably won’t help you much. You can increase your rankings, but you probably won’t get a lot of traffic or conversions.

If you sell camping supplies, this probably isn’t an authoritative site for your niche. If you are selling vintage punk concert flyers, this would be the case.

The last two sites are personal blogs that I found by doing some random searches.

The Life With Emily site has seen steady traffic over the past two years and receives about 1,500 visits per month, according to Semrush. The site ranks well for search terms such as “how to paint a front door”.


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If I had a DIY customer, I would like a link on this site. I think it might send me converting traffic and have authority for my client. It doesn’t have a DR 70 or DA 65, but it does have some relevance.

The latter site has lower metrics and very little traffic so I probably wouldn’t look for a link here. However, they seem to be doing a lot on social media which might be more valuable to them due to the industry.

They seem to have a thriving business. They have authority in the real world, and domain metrics can’t measure that.

Domain authority checkers lack real context

I decided to take a look at a few deindexed sites (I won’t reveal which ones because I don’t like dating people).

I come across these sites when link sellers send me large lists. I’m curious about their metrics and wonder why someone wants to sell me a link for $ 40.


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Site A is deindexed and has a DR 72, a DA 37, an AS 52 and a TF 21.

Site B is deindexed and has a DR 29, a DA 10, AS 25 and TF 21.

These two sites would be acceptable to most of my clients simply on the basis of their metrics. Site A would be highly desirable for everyone.

But they’re not indexed in Google, so the only way to meet them is if you access them from a link on another page, or if you know the domain for some reason.

How authoritative do you think a site is if Google removed it from its index?

These deindexed sites also have zero traffic and this has been the case for two years.

Have they been deindexed for two years? If so, how can they still look so good from a metric standpoint?

Since the measurements are good I could easily get a link on either site and many customers would just see a DR 72 and probably be happy.


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They would have no idea that these links were virtually worthless.

What other metrics can help assess true domain authority?


A site doesn’t have to have incredible traffic to help you rank, but your chances of people coming to your site from a link increase dramatically when there is more traffic.

Getting a link on a site with no traffic probably won’t help you much, and there’s usually a good reason why a site doesn’t have traffic.

If a link on a site like this happened organically it would be nice, but I wouldn’t spend time looking for one unless the reason it isn’t getting traffic is because it is brand new.

It’s okay to see dips, but in general you want to see constant or increasing traffic.

It's okay to see dips, but in general you want to see constant or increasing traffic.

Referring domains

A site that is heavily linked should theoretically be an authoritative site, but since the links can be so easily manipulated, I don’t think it’s that simple.


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You certainly can’t look at quantity over quality.

What you can do is take a look at the quality of these referral domains and see if they look like the kind of links you would want for your client or website.

Majestic data from referring domains.

Rankings and Ranking Keywords

If a site ranks well for the keywords it should rank for, that’s a good sign.

Good rankings also increase the chances of increasing traffic to the site, which in turn increases the chances of attracting more visitors to your site.

Ahrefs keyword ranking table.Moz ranking keyword data.

Metrics are just the beginning of determining authority

It’s critical to remember that none of these metrics come from Google, although many people still think Moz’s domain authority is representative of Google’s PageRank.


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Moz said that was not true and they tried to dispel the confusion, but the misunderstanding persists.

If you want to use metrics to help you gauge authority, I suggest you simply choose one and use it for trending purposes.

I have used each of these for various clients over the years, mainly because the client wanted to set a minimum metric for the sites we would get links to.

I like having a good initial guideline that my team can use to start evaluating a site, but I certainly don’t think any of these metrics should be used as the only data that makes you think a site has it. authority you are looking for.

More resources:

Image credits

Image 4: Majestic
All screenshots taken by author, March 2021


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