What is domain authority?
Domain authority is a 0–100 score that estimates how strong and trusted a website's backlink profile is. Higher usually means an easier time ranking — but the number is comparative, not absolute.
Updated 5 August 2026
The one-sentence version
Domain authority answers a single question: how well-connected is this website within the link graph of the web? A site that many trusted sites link to sits near the centre of that graph and scores high. A brand-new site with no inbound links sits at the edge and scores near zero.
What it actually measures
Every authority score — Moz's DA, Ahrefs' DR, our own — is a way of compressing a site's backlink profile into one comparable number from 0 to 100. The exact maths differ by tool, but they share an idea: a link from a strong site is worth far more than a link from a weak one. Our score uses harmonic centrality — a measure of how close a domain sits to every other domain through links.
Because the scale is logarithmic, the effort to climb rises steeply. Moving from 20 to 30 is ordinary; moving from 70 to 80 puts you among a few dozen sites on the entire web.
What a score really means, in real numbers
We computed the authority of every domain in an index of 118 million sites. The result is one of the steepest power laws in any dataset:
- 82.9% of all websites score below 10.
- Reaching 40 puts you in the top 0.06% of the web.
- Only 289 domains score above 70, and just 7 above 90.
- The median linked website has just two referring domains.
See the full breakdown in our study of domain authority across the whole web.
Domain authority vs page authority
Domain authority describes the whole site; page authority describes one URL. A strong domain gives its pages a head start, but a single page can outrank a stronger domain if it has focused, relevant links of its own. When people say “authority” without qualifying, they usually mean the domain-level score.
How to check it
You do not need a paid subscription. Paste any domain into our free domain authority checker and you will see its score, its referring domains, and where it falls in the distribution above — no account required.
Check any domain's authority — free
Frequently asked questions
What is a good domain authority score?
It depends on your competition, but the distribution is steep: across 118 million domains, 82.9% score below 10 and only 45 sites score above 80. A score of 20 already puts you ahead of roughly 97% of the web. Compare against the sites you compete with, not against giants like google.com.
Is domain authority a Google ranking factor?
No. Google does not use any third-party authority score. Domain authority is an independent estimate built by SEO tools from link data. It correlates with ranking ability because links matter, but Google has its own signals.
How do I increase domain authority?
Earn links from sites that are themselves authoritative and central to your topic. Quality beats quantity sharply — a few links from strong, relevant sites move the number more than dozens from weak directories.