Free domain authority checker

Common Crawl, a non-profit that crawls the web and publishes what it finds, turns each crawl into a graph: which domains link to which. Its graph of August to October 2026 holds 134,979,706 domains and ranks them by PageRank, the measure that gives a link more weight when the site making it is itself well linked (Common Crawl’s web graphs). Link Authority is a domain’s PageRank set between two ends: the lowest in the graph, which a domain no link reaches still gets, and the highest, the best-linked domain’s:

score = 100 × √(log(PageRank ÷ lowest) ÷ log(highest ÷ lowest))

A domain no link reaches scores 0 and the best-linked one 100. Most domains in the graph are barely linked: 47% of them score 0 and 68% under 5, so a site with a handful of links from small sites scores in single digits. Some points on the way:

• Top 0.001% of all domains: 75
• Top 0.01% of all domains: 66
• Top 0.1% of all domains: 51
• Top 1% of all domains: 36
• Top 10% of all domains: 14
• Top 25% of all domains: 6

The graph is public and so is the formula, so anybody can check a score. We picked PageRank over the graph’s other ranking because it agreed better with an independent one, Tranco’s research ranking of popular domains.

Until 10 November 2026 the score was a domain’s place in the PageRank ranking. Places among the domains with almost no links say little, since those domains are nearly tied, and a site with a few links came out around 25. The score now follows the PageRank itself, so it shows how far above an unlinked domain a site stands.

Moz’s Domain Authority and Ahrefs’ Domain Rating sum up a site’s links on a 100-point scale, each from that company’s own link index; Semrush’s Authority Score adds estimated traffic and spam signals to the links. They don’t agree with each other for the same site, and none of them publishes enough to check a number. Link Authority is ours, under its own name so it isn’t read as theirs, and it comes from data anybody can download. What makes a score good, and whether Google uses any of them: what is a good domain authority score?

• It isn’t a Google ranking. No search engine reads this score, or Moz’s or Ahrefs’. It summarises links, which are one thing among many that search engines weigh.
• A new or small site may not be in the graph. The graph only knows the links on pages Common Crawl crawled. A site nobody links to yet is shown as not in the graph, not as 0.
• A site on a shared platform has no score of its own. The graph counts every site on github.io, blogspot.com or notion.site as one domain, the platform’s. Rather than give such a site its platform’s score, the checker says where it lives.
• It changes with each release, not each day. These are the crawls of August to October 2026; we load a newer graph every few months.

Links from other domains, and above all from domains that are themselves well linked. The graph records whether one domain links to another, not how many times, so a thousand links from one site count as one site. Links you buy or swap at scale tend to come from sites nobody links to, which add little here and can cost you in Google.

The Trakis audit reads a site the way a search engine’s crawler does and reports each problem once, with the pages it covers, including whether search engines and AI assistants may read it. Free: create an account and add your site.