Domain Authority vs Domain Rating vs Revised Authority (What Each Score Measures)

Domain authority is a phrase with two meanings, and nearly all the arguments about it come from people using different ones. In the loose sense it means how strong a site's link profile is. In the strict sense it is Domain Authority, a trademarked score that belongs to Moz. Ahrefs has its own score and calls it Domain Rating. We have one and call it Revised Authority. All three run from 0 to 100. No two of them produce the same number for the same site, and Google reads none of them.

I wrote a version of this page a while back that was mostly about Moz's score. It was too long and it took Moz's word for a lot. This one takes each score on its owner's own definition, including ours, and then covers what you can compare and what you cannot.

Domain Authority, Moz's score

Moz's Domain Authority page opens with the definition: "Domain Authority (DA) is a search engine ranking score developed by Moz." On how it is built: "Moz calculates Domain Authority using a machine learning algorithm that evaluates multiple factors, primarily focusing on backlink data."

"Machine learning" carries two consequences that people miss. The score is trained to predict rankings rather than to count links, so it moves when Moz retrains the model even if nothing about a site's links has changed. And the inputs are private. You get the output and none of the workings.

On whether Google uses it, Moz is blunter than most people expect. "Domain Authority is not a Google ranking factor and has no effect on the SERPs." A little further down: "Unlike Google's ranking algorithms, Domain Authority is not a direct ranking factor." Both sentences are on Moz's own page, which is useful the next time an agency sells a DA increase as a ranking win.

On what counts as a good score, Moz says "There's no universally 'good' DA score since it's a relative metric", and offers that "A DA of 20 might be competitive for new or smaller websites, depending on your niche."

Domain Rating, Ahrefs' score

Ahrefs' glossary entry says "Domain Rating (DR) is a proprietary SEO metric by Ahrefs. It represents the strength of the website's backlink profile on a logarithmic scale from 0 to 100, with the latter being the strongest."

DR is a plainer instrument than DA. Ahrefs lists what goes in: "The number of domains linking to a website (referring domains)", "The DR of these referring domains", and "The number of websites the referring domain links to". It adds that "Nofollow links don't pass DR". There is no ranking prediction anywhere in it. It is a recursive link score over Ahrefs' own crawl, closer in spirit to PageRank than to Moz's model.

The scale is logarithmic, and Ahrefs puts it well: "The gap between DR 75 and DR 76 is much bigger than between DR 20 and DR 21." New sites climb fast at the bottom. The top is slow going.

Ahrefs also answers the ranking-factor question for everybody at once. Its help article on whether search engines use DA or DR says "There's no evidence that search engines use Domain Rating (or similar scores such as Domain Authority, the power of domain, etc) as a ranking factor at all."

Revised Authority, our score

Revised Authority, RA for short, is the number behind our domain authority checker. It is computed from the open Common Crawl web graph, and it is not Moz Domain Authority. We do not licence DA, resell it, or estimate it. I would rather say that three times than have someone read our number as Moz's.

The inputs are public, which is the point of it. Common Crawl publishes host-level and domain-level web graphs built from its crawls, and with each release it publishes a ranking of every domain in the graph on two measures. Harmonic centrality asks how close a domain is to the rest of the web. PageRank asks how much link value flows into it. We take a domain's position on each list and map it onto 0 to 100:

rankScore(rank, N) = 100 × (1 − log10(rank) / log10(N))
RA = round(0.65 × rankScore(hc_position, N) + 0.35 × rankScore(pr_position, N))

N is the number of domains in that release of the graph, about 118 million in the May to July 2026 release we hold now. The mapping is log-rank because link graphs are power-law distributed, and on a linear scale nearly every domain on the web lands in one band at the bottom.

Harmonic centrality carries 65 percent of the weight because on this graph PageRank pins a large share of domains to a floor value and stops separating them, while centrality stays spread out. PageRank keeps its 35 percent because it is the measure that rewards being linked by things that are themselves linked, and centrality alone does not capture that.

Every result shows both raw positions next to the score, and the release they came from. A rank out of 118 million domains is a fact you can check against Common Crawl's own files. The score is our reading of it.

Where RA falls short

Three limits that DA and DR do not have, and one they share.

It is a slice, not the web. Common Crawl samples. Domains the crawl did not reach, or reached thinly, rank lower than they would in a bigger index. Common Crawl's own page also notes that "all types of links are listed, including purely 'technical' links pointing to images, JavaScript libraries, web fonts, etc." A commercial index that filters down to editorial links will disagree with it at the edges.

It moves on Common Crawl's cadence, not ours. The score changes only when a new graph release is imported. Between releases it is fixed. That is good for a number you want to quote and bad if you earned a link last week and want to see it this week.

It has no subdomain split. The domain graph is aggregated at the registrable domain, so a blog on a shared host resolves to the host's score rather than its own. If you enter a subdomain and we hold no position for it, the tool says so and shows the parent's score with a note. Subdomains do not inherit their parent's authority, and the note exists so nobody reads it that way.

And it is not a Google ranking factor. None of the three are. Google's guide to its ranking systems lists "link analysis systems and PageRank" among the core systems and says PageRank "continues to be part of our core ranking systems". It names no third-party score and no site-level authority score of Google's own. Ahrefs quotes John Mueller saying Google doesn't "have anything like a website authority score". Every vendor here, us included, is estimating something Google computes privately and at the page level.

Side by side

What you can compare

A score against the same score. DA 40 against DA 60 is a real gap. DR 40 against DA 60 is two rulers, and it tells you nothing. Same for RA. A domain will score differently on all three because the indexes, the inputs and the maths all differ, and that is expected rather than a fault in any of them.

Within a niche. Moz's line about there being no universal good score holds for all three. DA 25 is strong for a local plumber and hopeless for a national newspaper. Pull the score for the sites already ranking for the queries you want and read yours against theirs.

Alongside referring domains. Referring domains is the count of distinct sites linking in, a plain count rather than a model. Two domains with the same authority score and referring-domain counts of 30 and 3,000 are not alike, whatever the score says. The backlink checker shows the count with the source pages and anchors behind it.

What you should not do with any of them

Decide with one. A composite score is a fine way to order a long list before reading it and a poor way to make the final call, because links, the thing all three count, are the thing that is easiest to manufacture. For an expired domain the final call comes from reading the referring domains as names and checking the archived history. The order I do that in is in how to evaluate an expired domain's link history.

Chase one. Google's spam policies define link spam as "the practice of creating links to or from a site primarily for the purpose of manipulating search rankings". Links bought to move a score are the textbook case. They will move DA and DR, since both count links. They will not move rankings, and Google says so on the same page.

What is a good domain authority?

There is no number, and every owner of a score says so. The honest answer for any of them is "higher than the sites you are competing with, and rising".

Since our mapping is public, here is what the RA scale means in practice. A domain at position one million in a 118 million domain graph scores about 26 on each rank. Position ten thousand scores about 50. Position one hundred scores about 75. The few hundred domains everyone on the web links to sit above that. The tool labels each result with the share of the graph it sits in, from "Top 0.01%" down to "Bottom 50%", because a percentile is easier to reason about than a score.

FAQ

Is Domain Authority a Google ranking factor? No. Moz's own page says "Domain Authority is not a Google ranking factor and has no effect on the SERPs." Google's published guide to its ranking systems lists PageRank and link analysis, not any vendor score.

What is the difference between domain authority and domain rating? Domain Authority is Moz's score, built with a machine learning model that predicts rankings from link data. Domain Rating is Ahrefs' score, a recursive measure of dofollow referring domains on a logarithmic scale. Different indexes, different maths, so the same site gets different numbers.

What is a good domain authority score? Moz says there is no universally good score because it is relative. Compare against the sites ranking for your target queries, not against a fixed threshold.

Is Revised Authority the same as Moz Domain Authority? No. Revised Authority is computed by us from the open Common Crawl web graph using the formula above. It measures a similar idea, link-based standing, but it is a different score on a different scale and the two will not match.

Why does my domain have a different score in every tool? Each tool crawls a different slice of the web and applies a different formula. Compare a score against the same score on other sites, not against a different score on the same site.

Expired domains keep the links they earned, which is why an aged domain can outscore a new one on any of these metrics. Our complete guide to expired domains covers where they come from and what to check. The Revised directory of expired domains with backlinks shows the referring-domain band, the linking sources and the archived history for every listing before you reveal a name, and the .com and Wikipedia source hubs are a reasonable place to start reading.