What is domain authority, and do AI assistants actually use it?

Somebody on your team has sent you a screenshot. A tool says your website has a domain authority of 23 and a competitor's has 41. Nobody is sure what the number means, but it feels like a school report and the mark is not good. Meanwhile a prospect mentioned last week that they asked ChatGPT for a shortlist of firms like yours and you were not on it.

Those two things are connected, though not in the way most agencies describe. Domain authority is a third-party estimate of how much the rest of the web vouches for your site. ChatGPT, Gemini, Claude and Perplexity do not read that score. They respond to what it measures: how many trusted, relevant sites mention and link to you, and what they say when they do.

The evidence behind the score does matter. In an SE Ranking study of 216,524 pages, reported by Search Engine Journal in November 2025, the number of referring domains (separate websites linking to a site) was the strongest predictor of whether ChatGPT cited it: sites with up to 2,500 referring domains averaged 1.6 to 1.8 citations, and sites with more than 350,000 averaged 8.4. This guide explains what the number is, why the tools disagree, what AI assistants actually respond to, and how a founder-led firm can build real authority without buying links.

#What is domain authority?

It is an estimate, made by SEO software companies, of how likely a website is to rank on Google compared with others, built almost entirely from links: how many other sites point to yours, and how trusted those sites are in turn.

The idea comes from academic citation. A paper cited by many others is probably worth reading; a paper cited by the leading researchers is worth reading closely. On the web, a link is a citation, and a link from a widely cited site counts for more.

Two things matter when you read the number. It is not Google's: Moz, which invented Domain Authority, says on its own explainer (March 2025) that "Domain Authority is not a Google ranking factor". And the scale gets harder as it rises: Moz says "it's easier to grow your score from 20 to 30 than it is to grow it from 70 to 80". So a competitor at 41 against your 23 is ahead, but not in the way the arithmetic suggests.

#Moz, Ahrefs or Semrush: why do the tools give different numbers?

Because each company crawls a different slice of the web and scores it with its own formula. Compare scores from one tool only, never across tools.

The differences are real. Ahrefs says DR "shows the strength of a website's backlink profile compared to the others in our database". Semrush says its Authority Score combines "Link Power", "Organic Traffic" and "Spam Factors". A site with plenty of links but little search traffic can score well on DR and poorly on Authority Score. Pick one tool, note the date, and compare yourself with the same five competitors each time.

#Does Google use a domain authority score?

Not the third-party ones. Whether Google has its own site-level measure is less clear than its public statements suggested.

For years Google's representatives denied using one; John Mueller said "we don't have website authority score", as Mike King of iPullRank noted in May 2024. That month, internal Google API documentation leaked, and Google confirmed to The Verge on 29 May 2024 that the documents were authentic. King's analysis found a feature called "siteAuthority" among Google's stored quality signals, while noting "we do not know specifically how this measure is computed or used".

For a founder, the practical reading is simple. Google appears to judge sites as well as pages, and whatever it measures is built from the same kind of evidence the tools approximate. The tools' numbers are still guesses at it.

#Do ChatGPT and the other assistants use the score?

No. None of the assistants checks an SEO tool before naming you. They respond to the evidence the score approximates, which is why the score still tells you something.

Your firm reaches an AI answer by two routes. The first is training: the model has read a large slice of the web, and firms that appear often on trusted sites, described consistently, are the ones it associates with a category. That changes only when the model is retrained, which takes months. The second is live search: ChatGPT search, Perplexity, Copilot, Gemini and Google's AI features search an index when a buyer asks, then read and cite pages. Search indexes weigh links, so well-linked pages are more likely to be retrieved, and that answer can change within weeks.

So does Ahrefs DR matter for ChatGPT? Not the number itself. The SE Ranking study found link-based scores, including its own trust score, correlated with ChatGPT citations, but correlation is not cause: sites with many referring domains tend also to be well known, frequently written about and full of substantial content. How AI cross-references what the web says about your firm covers how assistants weigh that outside evidence.

#Do brand mentions without a link help with AI search?

Yes. An AI assistant reads the text of a page. When a trade article names your firm and describes what you do, that sentence is evidence whether or not it links to you.

A mention helps in two ways, and a link adds a third:

• Live search: if the trade article is retrieved when a buyer asks a question, the assistant reads your name in a trusted context and can cite that article. Muck Rack's May 2026 analysis of more than 25 million links cited by ChatGPT, Claude and Gemini found 84% came from earned media.
• Training: text naming your firm on trusted sites is part of what future models learn from.
• A link, when there is one, also helps your own pages rank and be retrieved, because search indexes still weigh links.

So do not turn down coverage because it comes without a link, and do not chase links that come without coverage. In our view, a named, accurate description of your firm on a site your buyers read is worth more than a link from a site nobody reads.

#What domain authority do you need to appear in Google AI Overviews?

None. Google publishes no threshold, and the evidence argues against one. Ahrefs found in March 2026 that 38% of the pages cited in AI Overviews ranked in the top ten for the search, 31.2% ranked 11th to 100th, and 31.0% ranked outside the top 100, because Google runs several related searches for each question. A page on a modest site that answers a follow-up question well can be cited. What Google AI Overviews mean for your firm covers the rest.

#Do nofollow links count for AI visibility?

Partly. Since 2019, Google has treated nofollow, sponsored and ugc link attributes as "hints about which links to consider or exclude" rather than ignoring them outright. For AI assistants the attribute matters even less, because a nofollow link sits in text that names you, and the assistant reads the text. A nofollow mention in a respected trade title is worth having.

#Which mentions count most?

Relevance and trust matter far more than volume: one mention from your sector's leading trade title outweighs a hundred directory listings, and links from sites that exist to sell links can count against you. In our experience the sources that do most for a B2B firm are trade publications with editors, national and regional business press, professional bodies, and partners and clients who describe working with you. Whether backlinks still matter for ChatGPT goes into link quality, and whether ChatGPT trusts press coverage more than your own site compares earned, owned and paid sources.

#What does this look like for a real firm?

ID-Pal, an identity verification firm, shows that being known is not the same as being recommended. It scored perfectly on recognition: "6 of 6 correct answers to 'what does ID-Pal do?', every engine, every run." Yet "AI could describe ID-Pal. It never recommended it." Its case study sums up the gap: "AI knew who it was, and had no reason to recommend it."

Part of the problem was split authority. ID-Pal had bought NorthRow, a UK business verification platform, and "nothing on either site told Google or the AI engines that NorthRow and ID-Pal were the same company." The fix began with "About four hours of structured data work declaring NorthRow part of ID-Pal on both domains." Five industry pages were then rebuilt to answer the questions compliance leads ask. The results so far: "UK buyer questions where AI names ID-Pal: none in May, two in August, four in September 2026." And "AI answers still recommending NorthRow as a rival: six in May, one in September 2026."

#How do we build authority without buying it?

Four honest routes, the same whether your goal is Google, ChatGPT or both.

#Earn coverage in publications your buyers trust

Journalists and editors need expert comment, data and opinion. A founder who can explain what is changing in their sector, with a view, gets quoted, and each quote puts your name on a trusted site. Coverage on a respected title is read by live-search assistants as soon as it is indexed, often well before your own score moves. Which kinds of PR win work for a B2B firm shows how to do this without a large budget.

#Publish something worth citing

Original research, a benchmark, an annual survey of your clients, or a clear explainer of a regulation nobody has explained well will attract references without asking. Whether publishing your own research helps ChatGPT recommend you covers how.

#Turn relationships into references

Your professional body, key suppliers, software partners and proud clients will usually mention you if asked and given something easy to publish: a member profile, a joint case study or a partner listing.

#Refuse anything that looks manipulative

Bought links, private link networks, mass directory submissions and article-spinning services may nudge a tool's score for a while. They do nothing for whether an assistant trusts you, and if Google spots the pattern your organic visibility suffers too. When an agency promises a fixed number of links a month, ask where they come from.

#How should we use the score without being ruled by it?

Check it quarterly, in one tool, against the four or five firms buyers shortlist alongside you, and watch the direction of travel rather than the number. Pair it with the measure that matters: whether ChatGPT, Gemini, Claude, Copilot, Perplexity and Google's AI answers name you for the questions your buyers ask.

If the score is rising but the assistants still name competitors, the problem is usually how your site describes what you do or inconsistent facts across the web; why ChatGPT describes your firm wrongly covers that case. If the assistants have started naming you and the score has barely moved, ignore the score.

#What to do this month

1. List every trusted site that could plausibly mention you: trade titles, your professional body, partners, clients. Mark which already do, with or without a link.
2. Pick one piece of coverage to earn in the next sixty days, with a named contact and a specific angle.
3. Find and stop any link building you could not explain to a journalist without embarrassment.
4. Check your score and those of your five closest competitors in one tool, note the date, and set a reminder for three months.
5. Write down 20 to 50 questions your buyers ask and record which firms the main assistants name for them, so you judge progress by that.

#Frequently asked questions

#How do I check my domain authority for free?

Use one tool's free checker and stay with it: Moz's Domain Analysis for Domain Authority, Ahrefs' Website Authority Checker for Domain Rating, or a free Semrush account for Authority Score. Check your five closest competitors at the same time. The scores differ between tools, so never compare a Moz number with an Ahrefs one.

#What is a good domain authority score for a small B2B firm?

It depends on your sector and competitors. A specialist consultancy with a modest score may be the strongest firm in its niche, while a national firm with a higher one may lag its peers. Compare against the firms buyers shortlist alongside you, and treat the direction over a year as more meaningful than the number on any day.

#Can I improve my domain authority quickly?

Not by legitimate means. The score is built from other sites' decisions to link to you, so it moves at the pace those decisions are made, usually over quarters. What can change faster is what live-search assistants say about you, because a mention on a trusted page can be read as soon as it is indexed.

#Do paid directory listings help with AI recommendations?

A few relevant, well-kept directories help with consistency: your professional body's register, a respected sector directory, your Google Business Profile. Beyond that, paid directories add little, because a listing anyone can buy is not evidence that people who know your field chose to mention you.

#Should we hire a link-building agency?

Be cautious. Ask where its links come from, whether you could name the publications to a client, and whether the sites have real readers. An agency that earns editorial coverage and places expert articles is doing PR, and that moves both the score and the assistants.

#Does domain authority matter more than the content on our own site?

They work together. Outside evidence gets you considered; clear, specific pages let an assistant describe accurately what you do and for whom. A firm with high authority and a vague website gets named for the wrong things, and a firm with a clear site and no outside mentions rarely gets named at all.

Authority is earned in the places your buyers read, which is the work of Reputation That Wins. To see where you stand before worrying about any score, book a free Growth Review: 30 minutes with David Adams and three fixes in writing.

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