DR vs DA vs Open PageRank: which number to trust

Ahrefs Domain Rating (DR)

Ahrefs describes DR as the strength of a website’s backlink profile compared with the other sites in its database, on a 100-point scale (Ahrefs’ definition). A domain passes more to the sites it links to when its own DR is higher, and it splits what it passes evenly among all the domains it links to. DR looks only at links. Ahrefs says it doesn’t account for domain age or content quality (source).

The model is changing. From 1 December 2026 the default becomes DR4, which gives more weight to links from sites with organic search traffic and scores each subdomain separately. The DR4 guide covers that in detail.

Moz Domain Authority (DA)

DA is Moz’s score, on a range from 0 to 100, intended to predict how a site will perform in search rankings (Wikipedia’s summary). This guide doesn’t go into its inputs. Moz documents the method on its own site, and it’s worth reading before you rely on the number.

Semrush Authority Score (AS)

Semrush calls Authority Score a compound metric that grades the overall quality of a website or a webpage, on a scale of 1 to 100 (Semrush’s knowledge base). It is the broadest of the four. Besides link power, meaning the quality and quantity of backlinks, it uses the site’s estimated organic traffic and a set of spam checks. Those checks include having no organic rankings, an unnaturally high share of dofollow referring domains, an imbalance between links and organic traffic, and many referring domains on the same IP address or network. Semrush says it recalculates the score for all domains every two weeks.

Open PageRank

Open PageRank is a 0 to 10 score, shown to two decimals, computed from the web graph that the nonprofit Common Crawl releases (the published methodology). It is now run by Keywords Everywhere; its former address on DomCop’s site redirects there. The method combines a PageRank calculation over the whole graph with a count of referring domains that carry some weight of their own. The scale is logarithmic. All hosts are merged into their registered domain, so blog.example.com and example.com are one entry. The methodology says scores are recomputed when Common Crawl publishes a new graph, about once a month, and that it measures link authority, not traffic, revenue or content quality.

The four publishers’ own descriptions point to five differences.

• Different crawl data. Ahrefs and Semrush score from their own link databases. Open PageRank uses Common Crawl’s graph. A link one crawler has found and another hasn’t changes one score and not the other.
• Different inputs. DR is built from links alone. Authority Score adds estimated organic traffic and spam checks, so a site with many links and no search traffic can score well in one tool and poorly in another.
• Different units. DR4 rates a subdomain on its own. Open PageRank rolls every subdomain into the registered domain. For a page on a platform subdomain, the two can be far apart for that reason alone.
• Different scales. DR runs to 100, Authority Score from 1 to 100, Open PageRank from 0 to 10. Open PageRank’s scale is logarithmic, so a one-point step near the top represents far more links than a one-point step near the bottom. A 40 in one tool has no fixed equivalent in another.
• Different refresh cycles. Semrush documents a two-week cycle and Open PageRank roughly a monthly one. A new link can be counted in one score weeks before another. The guide on how long a backlink takes to show up covers the delays.

All of them are also relative. Your score describes your position among the sites in that tool’s database, so it can move when other sites gain or lose links, or when the publisher changes the model, as Ahrefs is doing now.

Google’s guide to hiring an SEO says that Google doesn’t evaluate or endorse third-party SEO tools, and that these tools don’t have access to Google’s internal ranking data (Google Search Central). That covers every score in this guide.

What Google does say about its own systems is narrower than a single site-wide number. Its guide to ranking systems says it has various systems that understand how pages link to each other, that PageRank is among them and remains part of its core ranking systems, and that how PageRank works has changed a lot since launch (source). The same page says ranking systems are designed to work at the page level, with site-wide signals also contributing.

The tool makers agree. Ahrefs’ help centre says there is no evidence that search engines use Domain Rating or similar scores such as Domain Authority as a ranking factor, and quotes Google’s John Mueller saying Google doesn’t have anything like a website authority score (source).

So links matter to Google, and these scores are outside attempts to summarise links. Raising a score is not the same as improving rankings. Ahrefs’ own figures for DR4 show the gap: across 10 million hosts, the correlation between DR4 and top 10 positions was 0.359 (source). That is a loose relationship, reported by the company that sells the metric.

• DR is the number launch directories and link sellers often quote. Use it when you need to check a quoted figure, and check the exact host. The DR checker shows DR3 and DR4 side by side for up to five domains or subdomains, using Ahrefs’ free API.
• Authority Score is useful when you suspect a link profile is inflated, because traffic and spam checks are part of the score. Semrush itself says it is best used to compare domains, not to judge good or bad on an absolute scale.
• Open PageRank is useful as a second opinion from data no SEO vendor controls, and for tracking a domain over time against a published method. The domain authority checker looks it up for up to five domains. Its weak spot is new sites: the methodology says a new or fast-rising domain may read low for a release or two.
• DA is worth checking when someone quotes it to you. Look it up in Moz’s own tool and compare it only with other DA figures.

1. Pick one tool per comparison. “Our DR is 35 and theirs is DA 50” says nothing. “Both checked with DR4 on the same day: 35 and 28” says something.
2. Compare with similar sites. A two-month-old product next to a ten-year-old publication will look weak on every scale. Compare with products of your age and category.
3. Check the host your link is on. If a listing sits on a subdomain, look up that subdomain in a tool that scores subdomains, and remember that Open PageRank will show the parent domain’s figure.
4. Write down the date and the model. “DR 31” recorded in October 2026 and “DR 22” recorded in December may be the same link profile under DR3 and DR4.
5. Look for agreement. If three scores rank five sites in roughly the same order, the order is probably sound. If one score is far out of line, find out why before you trust it or dismiss it.
6. Then look at the page. Open the page your link would be on. Check that it is indexed, that the link is in the HTML, and what its rel attribute says. The guide to verifying a directory link goes through those checks.

Since Google uses none of these scores, be careful with offers and reports that treat one as the goal. Two made-up examples of the pattern:

• Weak: “DA 70+ dofollow link, boosts your authority.” It names a score and a link type, and says nothing about who visits the page.
• Better: “Your product gets its own page in our weekly newsletter archive. Here are three recent ones and the search terms they show up for.” You can check every part of that yourself.

The same applies to your own reporting. “DR went from 12 to 19” is a fact about Ahrefs’ estimate. “Clicks from Google went from 40 to 110 a week” in Search Console is a fact about your site. If you need to show progress to someone, lead with the second kind.