Enter a domain : you get its authority score out of 100, its world rank and the number of domains linking to it. One domain or a list of 1000, on a public calculation you can redo yourself.
The domain alone is enough : no https://, no www. In list mode, up to 1000 domains, processed in batches of 50.
The 0 to 100 score is a harmonic centrality computed over the 1.14 billion links in the index, taken from Common Crawl's cc-main-2026-jun-jul-aug graph. It measures how close a domain is to the rest of the web when you follow links, and 119,722,885 domains are ranked in it.
Two practical consequences, and they are what makes the measurement worth having.
A thousand links bought from sites nobody cites bring you closer to no one : the score does not move. A single link from a site everyone cites does. A backlink counter goes up in both cases.
A domain can have few inbound links and high authority, because the ones it has come from the right place. That is why the referring domain count sits next to it, never instead of it.
The source files are downloadable by anyone. If a score surprises you, you can trace it back to the links that produce it. No proprietary index on the market allows that.
An authority checker that returns a single score leaves out the most interesting part. Each of the three columns answers a different question :
A domain well placed in the graph with no reach at all is a common case : directories and link farms look like established sites there. Crossing the three numbers is what lets you spot them.
The A list button takes 1000 domains, one per line. That is the everyday use of a DA checker : sorting a list before buying links, qualifying prospects, comparing a site with its competitors. The table exports to CSV in one click, with no row cap and no account.
Most free checkers limit bulk mode to ten rows, or keep it for their paid plan. Here the source data is public and reading it again costs nothing : there is no reason to ration it.
Saying so saves your time, and shows where the measurement stops.
The full domain ranking, by country and by extension, is available here. To find out who links to a site and from exactly which page, use the backlink checker.
A score that sums up where a site sits in the web's link network. It does not come from Google, which has published no such index since the public PageRank was retired in 2016. Every tool computes its own : Moz's Domain Authority, Semrush's Authority Score, Ahrefs' Domain Rating. Here the score is a harmonic centrality computed on the public Common Crawl link graph, and the calculation can be reproduced.
Type the domain in the field above. You get its score out of 100, its world rank and its number of referring domains, with no account, no credit card and no daily cap. List mode takes 50 domains at once, which most free DA checkers keep for their paid plan.
No, and no tool can return Moz's DA without going through Moz. Proprietary indexes are not comparable with one another : a DA 40, a Domain Rating 40 and an Authority Score 40 do not describe the same thing. What compares is the relative ranking of two domains inside one index. That is the use to make of this one.
By harmonic centrality over the full Common Crawl graph, then mapped onto a 0 to 100 scale. Harmonic centrality measures how close a domain is to the rest of the web when you follow links. A site cited by heavily cited sites is close ; a site cited by a thousand pages nobody reads is not.
Because it measures a position, not a volume. A thousand links from sites no one else cites bring you closer to no one : the score does not move. A single link from a site everyone cites does. That is the substantive difference with a plain backlink counter, which is why both numbers sit side by side.
That the domain does not appear among the graph's ranked domains. This covers very recent sites, sites no one links to, and domains whose inbound links the public crawl never recorded. It is not a score of zero : it is the absence of a measurement, and the two deserve to be told apart.
Authority tells you the position in the link graph. Reach, supplied by NicheObserver, estimates a domain's actual audience and goes far below the Top 1M of the usual lists. They complement each other : a directory can sit well in the graph while nobody visits it. Reach is fetched on a button, as it is the only one of the three that goes through a paid source.
Yes. List mode takes up to 50 domains per batch, one per line, and returns the full table in a few seconds. That is the common use : sorting a list before buying links, qualifying prospects, comparing a site with its competitors. The table exports to CSV in one click.