What Domain Authority is — and is not
Domain Authority (DA) is a score Moz gives a whole domain or subdomain. It predicts ranking chances from links. It is not a Google ranking input, and it is not proof that the site is the expert in a subject.
Some writers use the same phrase for subject credibility: a site people treat as the reference in its field. That idea is not the 1 to 100 number in an SEO tool. The number is Moz's.
- DA is Moz's model. Ahrefs Domain Rating and Semrush Authority Score are other companies' models of a similar idea.
- Google does not use the Moz score as a ranking factor.
- The scale is logarithmic, so 20 to 30 is a smaller step than 70 to 80.
- The number moves when Moz's link index moves, even if your site did not.
- Use it to compare domains on one query. Do not chase a round number for its own sake.
How Moz computes DA — the logarithmic scale
Moz runs a machine-learning model over its link index. The model asks how often domains with a similar link profile show up in Google, then squeezes that prediction onto a 1 to 100 scale. A new domain starts at 1.
Moz describes the inputs as links. What matters most is how many separate domains link to you, called linking root domains, and how strong those domains look in the same model. Ten links from one site do not count like ten linking domains.
The scale is logarithmic and comparative. The step from 20 to 30 is a smaller climb than the step from 70 to 80. If a very large site gains a vast number of new links, other domains can lose points even though their own links did not change.
Moz replaced the model in 2019 and called the result Domain Authority 2.0. A score saved before that rebuild is not on the same ruler as a score you read now.
How Page Authority differs from Domain Authority
Page Authority (PA) is Moz's score for one URL. Domain Authority is the score for the whole domain or subdomain. A strong domain can hold a weak page, and one well-cited URL can outrank the rest of a smaller site.
Moz also publishes Brand Authority, a third score about how widely a name is discussed. It does not replace DA or PA, and it does not say whether this URL should rank for this query.
- DA covers the domain or subdomain. Use it when you compare sites.
- PA covers one URL. Use it when you compare pages that could rank for the same query.
- Brand Authority covers how often the name is discussed. It is not a ranking forecast for a URL.
DA vs Ahrefs Domain Rating
Ahrefs Domain Rating describes backlink-profile strength. Semrush Authority Score mixes links with organic search data. Majestic Trust Flow is that company's own link score. None of these is Moz DA, and none of them is a Google ranking factor.
Wikipedia's article on this phrase cites research in which DA, Domain Rating and Authority Score tend to move together. The integers still disagree. Choose one tool, then compare every competitor in that tool.
| Score | Publisher | What the number describes |
|---|---|---|
| Domain Authority | Moz | Predicted ranking strength from the link index, on a logarithmic 1 to 100 scale |
| Page Authority | Moz | The same style of prediction for a single URL |
| Domain Rating | Ahrefs | Strength of the site's backlink profile |
| Authority Score | Semrush | Backlinks plus organic search data |
| Trust Flow | Majestic | Majestic's separate score. It is not Domain Authority |
Does Google rank by DA — the official stance
Moz says Domain Authority is not a ranking factor and does not move the results by itself. The score predicts link strength inside Moz's index. It is not a control Google gives site owners.
A Network Solutions article dated 20 May 2025 says Google has rejected a site-authority score of this kind. That is their report of Google's position. The test you can run is direct: when two pages fit the query, the clearer page can rank with the lower DA.
What a good Domain Authority score means
There is no universal good Domain Authority. Moz's own guide says a 30 can be excellent in one field and ordinary in another. The useful comparison is the domains already ranking for your query, read in the same tool on the same day.
The same Network Solutions article, dated 20 May 2025, offers rough bands: about 20 to 30 for many small sites, about 40 to 60 for growing brands, and 60 or above for the strongest domains. Those bands are not Google cutoffs.
Worked example. Page-one domains for your query sit between 18 and 32 in Moz, and your domain is 22. You are inside that set. Chasing 60 because a national news site shows 60 does not decide whether your page answers the query.
How to check Domain Authority
Read the number in Moz. Link Explorer and Moz's free Domain Authority checker accept a domain. MozBar shows DA in the browser while you look at a page. Moz Pro's Domain Overview places DA next to keyword data.
Enter the bare domain when you want Domain Authority, and use the same host each time, with or without www. An Ahrefs or Semrush screen is a different score. Do not average the three numbers into one.
What actually moves rankings besides Domain Authority
Google orders pages that match the query, that relevant sites cite, and that it can crawl. Domain Authority compresses the citation side inside one vendor's index. It does not record whether this URL answers the question.
A narrow query can rank a modest domain when the page is the clearest answer and few strong pages compete. A high-DA page about a different topic should not rank. That gap is the difference between the Moz metric and the ranking.
WebJi® SEO services name the pages, cities and reports in the monthly work. They do not sell a DA target or a guaranteed position. If the choice is paid clicks versus organic, read Google Ads versus SEO before you shift budget because a score looked low.
How to grow DA legitimately — content, links, digital PR
Domain Authority rises when Moz's next index sees more diverse, relevant linking domains. You cannot set the number in a hosting panel. Legitimate movement is slow because the scale gets steeper as the score gets higher.
- Record DA for your domain and for the domains on page one, in Moz, on the same day.
- Publish a page a relevant site can cite: original data, a procedure, or a sourced comparison.
- Earn links from sites in that field. Do not buy them. A few relevant domains beat a long list of unrelated ones.
- Link internally to the URLs you want found, with anchors that name the destination.
- Disavow links that are obvious spam, and leave unfamiliar links alone until you know what they are.
- Serve the site on HTTPS and keep the important URLs indexable. That does not add DA points. It lets those URLs earn links.
- Read DA again after Moz updates its index. Judge the gap versus page one, not the change versus last month alone.
If you want that citation work under a written scope, see link building. Hosting changes and free migration do not raise Domain Authority. WebJi® does not promise a score.
Why DA fluctuates and drops
A drop is often the index, not a punishment. Moz's crawl can gain or lose linking domains between updates. Links you lost, links the model does not treat as ranking-like, and big gains at other sites all move a comparative score.
Spammy links can pull the number down. A model change can do it too, which is what Domain Authority 2.0 did in 2019. A domain that is about to expire is a separate problem: if the name lapses, the site can go offline, and the score is not the thing to fix first.
Frequently Asked Questions
What is domain authority in SEO?
Domain Authority is Moz's 1 to 100 score for how likely a domain is to rank, based mainly on its backlinks. It is a third-party estimate. Google does not use it as a ranking factor.
How is domain authority calculated?
Moz trains a model on its link index. Linking root domains and link quality do most of the work, then the result is mapped onto a logarithmic 1 to 100 scale. New domains start at 1. Domain Authority 2.0, released in 2019, changed that model.
Is a Domain Authority of 30 good?
It is good only next to the domains ranking for your query. Moz says 30 can be strong in one niche and weak in another. Bands such as 20 to 30 for small sites are other writers' labels, not a Google pass mark.
Does Google use Domain Authority for ranking?
No. Moz states that Domain Authority is not a Google ranking factor. A lower score can still rank when the page matches the query and the competing set is small.
How do I check my Domain Authority?
Look it up in Moz Link Explorer, Moz's free Domain Authority checker, or the MozBar extension. Read Page Authority when you are comparing one URL. Do not mix the Moz number with Ahrefs Domain Rating or Semrush Authority Score.
What is the difference between Domain Authority and Page Authority?
Domain Authority scores the whole domain or subdomain. Page Authority scores one URL. Both are Moz predictions from link data. Neither is a setting inside Google.
Why did my Domain Authority drop?
Common causes are a Moz index update, links you lost, links the model discounts, or other sites gaining links on a comparative scale. Check whether page-one competitors moved before you treat the drop as a penalty.
How do I increase Domain Authority without buying links?
Earn citations from relevant sites to pages worth citing, then wait for the next Moz crawl. Buying links can damage how search engines trust the domain. No hosting change sets the number.