Website Authority Checker
A website’s authority score estimates how much link equity its domain has earned. Enter any domain to get its Open PageRank, a 0–10 score computed over Common Crawl’s public link graph, plus its global rank, referring domains, and every monthly observation back to 2018. Free, no account — and it is not Moz DA or Ahrefs DR, which is explained below.
What this number actually is
Three things worth knowing before you act on any authority score, ours included.
A public graph, not a private one
Open PageRank runs the original PageRank algorithm over Common Crawl’s domain-level web graph — about 90 million domains joined by 2 billion links, released as open data. You can download the same graph and check the arithmetic.
Not Domain Authority, not Domain Rating
Those are proprietary metrics over private crawls, licensed per call. No free tool can compute them. This is a different number measuring a similar idea, and conflating the two would make every comparison you draw wrong.
A relative measure with a monthly clock
The graph rebuilds monthly and the scale is roughly logarithmic, so read your position against direct competitors and read the trend. An established domain carries a monthly series back to 2018; a single absolute score, on its own, decides nothing.
From domain to a number you can use
Four steps, about a minute — no account required.
- 1
Enter a domain
Paste any domain — yours, a competitor’s, or a link prospect’s. A full URL is fine: it is reduced to the registrable domain, because the link graph is keyed by domain, not by page.
- 2
Read the score
You get an Open PageRank from 0 to 10, the domain’s global rank in the graph, and the number of referring domains the graph counted.
- 3
Read the trend, not the number
A single score is close to meaningless in isolation. The monthly history is the useful part, and for an established domain it runs back to January 2018: climbing, flat, or falling over years tells you whether anything you did worked. A domain new to the graph has one observation and no trend yet, which is itself informative.
- 4
Compare against the set that matters
Check the three or four competitors you actually lose deals to. Authority is only ever a relative measure, and “good” is entirely a function of your niche.
Common questions
A website authority score is a single number estimating how much link equity a domain has accumulated, usually on a 0–10 or 0–100 scale. It is computed by running a ranking algorithm — normally a variant of PageRank — over a crawl of the web’s hyperlink graph. It is an estimate produced by whoever built the index, not a figure published by any search engine.
No, and nothing free can be. Domain Authority (Moz), Domain Rating (Ahrefs), and Authority Score (Semrush) are proprietary metrics computed over each company’s own private crawl. Reproducing one would mean licensing that company’s API. This tool reports Open PageRank instead: the same idea, computed over a public link graph anyone can download and check. The numbers correlate loosely but are not interchangeable, and a tool telling you it returns “DA” for free is either reselling Moz or inventing the figure.
Open PageRank is classic PageRank recomputed over Common Crawl’s domain-level web graph — roughly 90 million registrable domains connected by about 2 billion links, rebuilt from Common Crawl’s monthly crawls and published as open data. Common Crawl also publishes harmonic centrality for the same graph, which is more resistant to link spam than PageRank. You do not have to take our word for any of it: the graph and the rank files are public on AWS Open Data, and the tooling that builds them is open source.
The underlying graph is rebuilt monthly, so a score moves at most once a month and one observation is one month. The series runs back to January 2018, which is about 105 observations for a domain that has been in the graph throughout. If you published a link yesterday, do not expect to see it today — and be suspicious of any tool that shows you a same-day change in a monthly metric.
Not this one, and not any third party’s. Google has stated repeatedly that it does not use Moz’s, Ahrefs’ or Semrush’s scores, none of which it has access to. Google does evaluate signals at site level internally, but those are not public, not published as a number, and not what this tool measures. Treat an authority score as a competitive yardstick for your own planning, never as a prediction of where you will rank.
Only relative to your competitive set. Open PageRank is roughly logarithmic — most indexed domains cluster low, and each additional point is substantially harder to win than the last — so comparing a local trades business to a national publisher tells you nothing useful. Check the three or four sites competing for the same queries and read your position among them.
Earn links from domains that themselves have authority, which is the only input the algorithm has. There is no configuration change, meta tag, or file you can publish that moves a link-graph metric. If your goal is being cited by AI answer engines rather than ranked, links are only part of it: run the AEO audit, which checks crawlability, structured data, and answer readiness alongside it.
It is free and needs no account. The lookup runs against the Open PageRank API on a metered free tier, so heavy automated use may be rate limited. If a lookup fails you will be told which of those happened rather than shown a zero.