Domain Authority Explained: What It Is and Why It’s Often Misunderstood

Domain Authority is one of the most widely-quoted and most misunderstood metrics in SEO. Ask ten business owners what Domain Authority means and you will get ten different answers, most of them assuming it is a Google score. It is not. This article explains what Domain Authority actually is, who calculates it, how it differs from Ahrefs’ Domain Rating, why neither is a ranking factor, and how to use these scores correctly without falling into the traps that catch most SMBs and even some agencies.

What Is Domain Authority?

Domain Authority (DA) is a third-party score from 0 to 100 invented by Moz, the SEO software company. It predicts how likely a website is to rank on Google’s first page for any given query, based on the strength and quantity of its backlink profile. Higher DA means more and better backlinks; lower DA means fewer or weaker ones. The score is logarithmic, which means moving from DA 20 to DA 30 is significantly easier than moving from DA 50 to DA 60.

Crucially, Domain Authority is not a Google metric. Google’s John Mueller has stated publicly multiple times that Google does not use Domain Authority, Domain Rating, or any third-party authority metric in its ranking algorithms. DA is Moz’s best attempt to model what Google might do based on link signals, but it is an outside-in estimate, not an inside view.

How Domain Authority Is Calculated

Per Moz’s Domain Authority documentation, DA is calculated using a machine learning model that incorporates more than 40 link-related signals, including:

• The number of unique referring domains linking to the site.
• The quality of those referring domains (their own DA scores).
• The diversity of the backlink profile.
• The ratio of follow to nofollow links.
• Spam signals on the linking domains.

Moz periodically retrains the model against Google search results, which is why DA scores sometimes shift sitewide even when nothing changes on a specific site. The recalibrations make DA more accurate as a relative measure but also produce confusing year-on-year changes for individual domains.

Domain Authority vs Domain Rating (Ahrefs DR)

The other widely-cited authority metric is Ahrefs’ Domain Rating (DR), also a 0-100 score. The two look similar but measure different things:

• Moz Domain Authority models overall ranking probability using 40+ link factors. Updates approximately monthly.
• Ahrefs Domain Rating measures backlink profile strength only, focused on unique referring domains and their own DR values. Updates within 15-30 minutes of Ahrefs’ crawler discovering changes.

According to Ahrefs’ own documentation, DR is a purer measure of backlink authority. DA tries to be a broader ranking-potential predictor. In practice, the two scores rarely match for the same domain — DR tends to run higher because Ahrefs has a larger index of backlinks (35 trillion+ as of 2026 vs Moz’s smaller link database).

Is Domain Authority a Google Ranking Factor?

No. Google has been categorical about this since at least 2016. John Mueller, Gary Illyes and several Google search representatives have stated in talks, AMAs and Twitter posts that Google does not use DA, DR, or any third-party authority score. Google has its own internal scoring system (formerly called PageRank, now part of a broader system that includes signals Google does not name publicly), and the scores Moz and Ahrefs assign are external estimates.

What is true: Google heavily uses link signals as part of its ranking system, and high-DA/DR sites typically rank well because they have the kind of link profile Google rewards. The correlation between DA and ranking is real; the causation is not.

What Is a “Good” Domain Authority Score?

Because DA is logarithmic and relative, “good” depends entirely on the niche. Rough benchmarks:

• DA 1-10 — brand-new sites, very few backlinks. Most newly-launched AU service business sites sit here.
• DA 10-30 — established small business sites with some natural mentions and directory listings.
• DA 30-50 — established mid-market businesses with active marketing, blog content earning links, and a few high-profile mentions.
• DA 50-70 — major brands, news sites, agencies and well-known industry publications.
• DA 70-100 — global publishers, major news outlets, government and educational institutions.

For an Australian SMB, DA in the 25-40 range after 12-24 months of consistent SEO work is realistic and competitive. Chasing DA above the level of your direct competitors is wasted effort.

How to Improve Domain Authority

The honest answer: you do not improve DA directly, you improve the underlying backlink profile, and DA reflects the change. The tactics that move the score:

• Earn links from high-DA domains — one link from a DA 70 industry publication is worth dozens from DA 10 directories.
• Diversify referring domains — 50 links from 50 different sites beats 500 links from 5 sites.
• Build content that earns links naturally — original research, data studies, free tools, comprehensive guides.
• Get cited in news and industry media — digital PR is the most reliable lever for AU businesses.
• Clean up toxic links if there is evidence of negative SEO — but skip routine disavowing; Google generally ignores low-quality links rather than penalising for them.

What does not move DA: directory submissions in bulk, link exchange schemes, PBN links, comment spam, social profile links, or paying for low-DA links.

Why Your Domain Authority Score Suddenly Changed

If your DA dropped overnight without losing any links, it was almost certainly a Moz model recalibration. Every 6-12 months Moz retrains the underlying machine learning model, which shifts every DA score in the index. The two recent recalibrations (2023 and 2024) compressed scores at the top end and moved many sites down 5-15 points. The site did not get worse; the measurement got recalibrated. Always check year-on-year DA changes against the recalibration dates before assuming a link audit problem.

Should You Care About Domain Authority?

DA is useful for:

• Comparing competitors at a glance.
• Vetting potential link prospects (would you accept a guest post from this DA-12 site? probably not).
• Tracking general link-building progress over 6-12 month windows.

DA is misleading for:

• Predicting ranking on a specific keyword — page-level signals, content quality, intent match and topical authority matter more.
• Goal-setting — “increase DA from 25 to 35” is a vanity goal, not a business goal.
• Judging individual page authority — that is what Moz’s Page Authority (PA) and Ahrefs’ URL Rating (UR) are for.

Rank Haus tracks DA for clients as one of many context metrics, not as a KPI. The KPI is organic conversions, not a 0-100 score from a third party.

Common Domain Authority Misconceptions

• “My DA went up so I am ranking better.” Sometimes; sometimes not. DA changes from Moz recalibrations are unrelated to live ranking.
• “My competitor has higher DA so I cannot beat them.” Often false. Page-level optimisation, search intent match, content depth and freshness all override DA at the page level.
• “I need DA 50 to rank.” Plenty of DA 20-30 sites outrank DA 50+ competitors on long-tail and intent-specific queries.
• “Buying high-DA links will boost my DA.” The link might be counted, but if it is from a known link-selling network, Moz’s spam filtering will discount it and you risk Google penalties.

Frequently Asked Questions

Is Domain Authority a Google ranking factor?

No. Google does not use Domain Authority or any third-party authority metric. DA is Moz’s estimate of ranking potential, not a signal Google’s algorithm sees.

What is the difference between DA and DR?

DA is Moz’s 0-100 score that predicts overall ranking probability using 40+ factors. DR is Ahrefs’ 0-100 score that measures backlink profile strength only. DR usually scores higher than DA for the same domain because Ahrefs has a larger backlink index.

How do I check my Domain Authority?

Free options include Moz’s Link Explorer (limited monthly queries), the MozBar browser extension, and Ahrefs’ Free Backlink Checker (shows DR). Paid Moz Pro and Ahrefs subscriptions give full access.

Can Domain Authority go down?

Yes. Most commonly from Moz’s periodic model recalibrations rather than from anything you did or did not do. Losing major backlinks also drops the score.

How long does it take to build Domain Authority?

Realistically, 12-24 months of consistent link-earning effort to move from DA 0-10 to DA 25-35 for a new AU SMB site. Moving from DA 30 to DA 50 typically takes another 18-36 months because the curve flattens.

Should I worry about Page Authority (PA) too?

PA is similar to DA but for an individual page rather than the whole domain. It is more useful than DA for understanding why a specific page ranks (or does not), but the same caveats apply — it is a Moz metric, not a Google signal.

Want Help Building Real Authority?

Chasing DA scores is a distraction. Building genuine authority — through citations, expert content, digital PR and real industry recognition — is what moves rankings, traffic and revenue. Get in touch with Rank Haus for an honest authority-building plan focused on the metrics that matter.