Does Google use Moz Domain Authority?

No. Domain Authority is Moz's own 0-100 estimate of ranking likelihood, built from a link graph Moz crawls itself. Google representatives have said publicly and repeatedly that Google does not use Moz's Domain Authority, or any third-party authority score, as a ranking factor. Treat DA as a comparative tool, not a signal Google reads.

Why do Ahrefs, Moz, and Semrush give different authority numbers?

Because each vendor crawls its own index and weights links its own way, then scales the result from 0 to 100. Domain Rating, Domain Authority, and Authority Score are separate estimates of similar ideas, not one shared measurement. That is exactly why you should never compare a score from one tool against a score from another.

Why domain authority is a vendor metric, not Google's

Guide · Market Growth · 4 min read · last verified 2026-07-23

Reviewed before publication Editorial board Independent commercial review

In shortDomain authority (DA) is a 0-100 score created by the SEO vendor Moz to predict a site's likelihood of ranking, based on its own crawl of the web's link graph. Google does not calculate or use it; Ahrefs' Domain Rating and Semrush's…

Domain authority is a score built by a third-party SEO tool — Moz — to predict how likely a page on a site is to rank. It runs 0 to 100, it is calculated from a link graph the vendor crawls itself, and Google neither produces it nor consumes it. Google's own Search Advocates have said in public, more than once, that there is no "domain authority" score inside their ranking systems. So when a report hands you a DA of 42 and calls it your "authority," read it as one company's model of the web — useful as a relative gauge, misleading the moment you treat it as a dial Google is turning.

What is domain authority, exactly?

Moz introduced Domain Authority as a convenience: a single number that compresses a messy backlink profile into something you can compare and chart. It is trained to correlate with ranking, not to reproduce any Google signal. Ahrefs shipped its own version, Domain Rating; Semrush shipped Authority Score; Majestic has Trust Flow and Citation Flow. Each vendor crawls its own index, weights links its own way, and lands on a figure. That is the first tell: if the number were a property of your site, every tool would return the same value. They don't, because each is a separate estimate.

The scores are also relative — moving from 20 to 30 is ordinary, moving from 70 to 80 is rare and hard. A rising DA usually means the vendor found more or stronger links pointing at you since it last crawled. That can be worth knowing. It is still a vendor's guess about a link graph, refreshed on the vendor's schedule.

Does Google use domain authority?

No — and this is the part worth being precise about. Google representatives have stated repeatedly and publicly that Google does not use Moz's Domain Authority, or any third-party authority score, as a ranking factor. Google has described having some site-wide understanding of quality, but that is not the same object as a purchased 0-100 metric, and Google does not ingest vendor scores.

How Google actually weights links and sites is not publicly observable. Anyone who tells you the exact contribution of "authority" to a given ranking is offering a hypothesis, not a measurement — including the vendors whose living depends on the number. The honest position: links matter, site-level reputation plausibly matters, and the specific machinery is a black box. The precise contribution of any link is a hypothesis worth testing, never a fact to bank — and links behave differently again inside the AI answer engines buyers now use.

|---|---|---|---|

| Domain Authority (DA) | Moz | 0-100 | Likelihood of ranking, from the link profile |

| (a Google "authority score") | — | — | Does not exist as a public, usable metric |

Why do so many vendors sell their own version?

Because a single comparable number is genuinely useful for the jobs SEO tools are hired to do — triaging link prospects, checking why a competitor outranks you, sanity-checking an outreach list. A relative score is a fine instrument for relative questions. The trouble starts when the number escapes its lane: into board decks as "our authority," into vendor pitches as a promise, into strategy as a target to raise for its own sake. A metric built to rank prospects becomes a goal, and the goal quietly replaces the outcome it was supposed to predict.

So is the score useless?

Not at all — it is just mislabeled. Used well, a vendor authority score is a comparative lens: is this prospective link source stronger or weaker than that one; did a competitor's profile change; is this a plausible place to earn a mention. Used badly, it becomes a vanity target you optimize toward while the thing that pays — buyers finding you when they ask a real question — goes unmeasured.

Two rules keep you honest. First, never compare scores across tools; a DR from Ahrefs and a DA from Moz are different rulers. Second, never report a vendor score as if it came from Google. The moment "authority" leaves the analyst's screen for a leadership conversation, relabel it: "Moz's estimate of our link strength," not "our Google authority."

What should you measure instead?

The question that actually pays is not "what is our authority score" but "when our buyers ask the questions that precede a purchase, do they find us — and who do they find instead?" That measurement doesn't live on a 0-100 dial. It lives in the public pages that rank for those questions: the comparison articles, buyer guides, and review roundups your prospects actually read.

This is where a vendor score and buyer visibility part ways. You can lift your DA and still be absent from every page that answers your category's key questions. You can have a modest DA and be cited across the exact sources buyers trust. Magrios measures the second thing — presence in the top-ranking public sources for real buyer questions, with a link behind every finding — precisely because a score you can't open is a score you can't act on.

A number is only as good as the decision it improves. Domain authority improves relative link decisions. Ask it to stand in for how Google sees you, or for whether buyers find you, and it will quietly mislead a room full of people who trusted it because it looked like it came from the search engine. It didn't.