What Is Domain Authority? A Moz Metric, Not a Google One

Aug 01, 2026 · SEO Glossary

Ask Google whether it uses Domain Authority and you'll get the same answer its search advocates have given for a decade: no. Not the Moz metric, and not an internal equivalent called "domain authority." So the first thing to understand about this term is jurisdictional: DA is a score invented, calculated, and owned by Moz, an SEO software company. It lives in Moz's index, not in Google's ranking systems.

What is Domain Authority, then? It's Moz's 1–100 prediction of how likely a domain is to rank in search results, computed almost entirely from the domain's backlink profile — how many sites link to it and how strong those linking sites are — using a machine-learning model trained against actual SERPs. It's an estimate about Google, from the outside. That's a useful thing to have, as long as nobody confuses the thermometer with the weather.

How the Domain Authority number is built

Moz crawls the web, builds a link index, and for each domain feeds link-based features (linking root domains, total links, quality and spam signals of the linkers) into a model that predicts ranking likelihood. Details worth knowing because they change how you read the score:

• The scale is logarithmic. Moving from DA 20 to 30 requires modest link growth; moving from 70 to 80 requires enormous growth. Equal increments are not equal effort.
• Scores are relative and recalibrated. Your DA can drop with no change on your site, simply because high-end domains gained links and the curve shifted. A falling score isn't necessarily a falling site.
• It's domain-wide. One strong section inflates the score for every page, including empty ones. Moz's Page Authority exists for URL-level estimates.
• It only sees links. Content quality, relevance, freshness, user experience — the things that dominate actual rankings — are invisible to it.

Every tool has one, and they don't agree

The same site can plausibly show DA 42, DR 55, and AS 38, because each vendor has a different crawl, index, and formula. None is more "correct" — they're different rulers. The practical rule: never compare scores across tools, and never compare across time without asking whether the vendor recalibrated.

What DA is genuinely good for

Used as designed — comparatively — it earns its keep:

1. Sizing up a SERP. If every page ranking for your target term sits on DA 70+ domains and you're at 25, that's real information: you'll likely need a longer-tail entry point, and winning that head term is a multi-year link project.
2. Triaging link prospects. Sorting five hundred outreach candidates by DA is a reasonable first-pass filter before human review.
3. Tracking direction, coarsely. Your own DA moving from 20 to 35 over two years says your link acquisition is compounding. Month-to-month wiggles say nothing.

Where chasing the number goes wrong

The failure mode is Goodhart's law: the moment DA becomes the goal, behavior warps.

• Buying links "to raise DA." Link sellers advertise placements on "DA 50+ sites" precisely because the metric is easy to game with sites that have inflated link profiles and zero real traffic. Google ignores or penalizes such links; your DA may rise while nothing real improves.
• Reporting DA as an outcome. Agencies sometimes report DA growth to clients as if it were traffic. It isn't. Rankings, clicks, and conversions are outcomes; DA is a loose proxy for one input.
• Ignoring relevance. A DA 30 site in your exact niche linking to you is worth more than an off-topic DA 70 link, both for rankings and referrals. The single number hides this entirely.

Notice also what the metric structurally can't see: whether your pages return errors, whether your content is thin, whether your E-E-A-T signals hold up, whether your internal linking distributes strength to the pages that need it. Two sites with identical DA can have wildly different technical health — which is why pairing any authority metric with an actual crawl of your site's structure and errors gives a far more honest picture of ranking readiness than the score alone.

If you want the number to rise anyway

There's no shortcut that isn't self-defeating; the input is links from real, distinct, reasonably strong domains. That means content worth citing (original data, genuinely useful tools and guides — the cornerstone content pattern), digital PR that earns coverage, and unglamorous reclamation: finding unlinked brand mentions and broken links pointing at your site. Growth measured in quarters, not weeks. And keep the frame straight the whole way: the links are the asset. The DA is just the gauge needle.

If you want a tracking metric that's harder to fool, watch referring domains directly — the count of distinct sites linking to you, filtered to ones with real traffic. It's the main raw input behind every authority score, it doesn't get recalibrated out from under you, and a chart of referring domains over two years tells the same story as DA without the vendor's model in between. Pair it with the rankings and clicks the links were supposed to produce, and you've got a reporting stack where every number means something.