No. Domain Authority (from Moz) and Domain Rating (from Ahrefs) are proprietary third-party metrics built from each tool’s own independent link-graph crawl and its own scoring algorithm, and they are explicitly not derived from or validated against Google’s actual internal ranking systems. Google has repeatedly stated, through Mueller and other representatives in public forums, that it does not use these third-party metrics at all, and that they function as rough, useful-for-relative-comparison heuristics for practitioners rather than as accurate stand-ins for how Google’s own systems actually evaluate a given backlink’s contribution.
What DA and DR actually measure
Domain Authority and Domain Rating are each computed from a proprietary crawl and link index maintained independently by Moz and Ahrefs respectively, not from any data Google shares or any algorithm Google discloses. Each tool crawls a large but necessarily incomplete slice of the web’s link graph (no third-party crawler indexes the web as comprehensively or continuously as Google itself does), and each applies its own scoring methodology to translate a domain’s link profile within that index into a single 0-100 score. These scores are explicitly designed by their respective companies as comparative, practitioner-facing heuristics, useful for getting a rough sense of a domain’s relative link authority compared to another domain measured by the same tool, not as an attempt to reverse-engineer or replicate Google’s actual ranking computation.
Because DA and DR are each built from different underlying crawl data and different proprietary formulas, they routinely disagree with each other for the same domain, sometimes substantially, which is itself a useful reminder that neither is measuring some single objective “true” authority value; each is measuring authority as defined by that specific tool’s own methodology and data.
Why Google has explicitly disclaimed these metrics
Mueller and other Google representatives have stated directly, in various public Q&A and office-hours settings over the years, that Google does not use Domain Authority, Domain Rating, or any similar third-party composite metric in its ranking systems. This is a straightforward, repeatedly confirmed point: these scores are entirely external constructs, computed by companies with no access to Google’s actual index, crawl data, or ranking algorithm, and Google’s systems have no mechanism by which they would incorporate a third-party score computed outside of Google entirely.
Google’s own actual evaluation of a backlink’s contribution, to the extent it’s understood at all, is described as considering a range of factors beyond what a single composite score could capture: relevance and topical context, the nature and quality of the linking page and site, anchor text, and much more that isn’t disclosed in a way that would allow any third party to compute an equivalent score independently. A single number attempting to summarize all of that into one comparable figure is, by construction, a simplification that Google’s own more granular and non-public evaluation doesn’t work the same way.
Why DA/DR are still genuinely useful, just not for what this myth claims
It would be an overcorrection to conclude DA and DR are worthless. As relative, comparative heuristics within their own respective tool’s index, they’re genuinely useful for practical tasks: quickly triaging a large list of potential link-building prospects to prioritize outreach toward domains that appear (by that tool’s methodology) to carry more authority, get a rough directional sense of whether a competitor’s overall link profile looks stronger or weaker than your own, or flag domains that look anomalously low-authority as potentially lower-priority or even spam-adjacent link sources. These are legitimate, practical uses of the metrics as comparative sorting tools.
What DA and DR are not reliable for is the specific claim in the question: using either score as an accurate proxy for the actual ranking value Google itself would assign to a link from that domain. A domain with a high DA or DR score isn’t guaranteed to pass strong ranking value for any specific link, because Google’s actual evaluation weighs relevance, context, and many other factors a single third-party composite score doesn’t and can’t capture, and a domain with a comparatively low third-party score might still provide genuinely valuable, topically relevant signal that Google’s systems weigh more favorably than the score alone would suggest.
Practical implication
Use Domain Authority or Domain Rating as a rough triage and prioritization tool, useful for sorting large prospect lists and getting directional comparative signal, but never present either score to a client or stakeholder as if it represents Google’s actual assessment of a link’s ranking value, and never make a link-acquisition or link-rejection decision purely on the basis of a DA or DR threshold without also evaluating the actual topical relevance, context, and quality of the specific linking page and its relationship to the content it would link to. The score is a proxy for a proxy, useful for efficiency, not a substitute for evaluating what Google’s systems are actually understood to weigh.
A worked example of DA/DR diverging from actual ranking value
Suppose a link-building team is choosing between two prospects for a page about commercial HVAC maintenance: Site A, a general-interest lifestyle blog with a DA of 68 that occasionally covers home topics among hundreds of unrelated subjects, and Site B, a niche trade publication for commercial building maintenance with a DA of 31. Under a DA-threshold rule, Site A looks like the obviously stronger acquisition target. But Site B’s entire readership and editorial focus is topically adjacent to the linked page, while Site A’s is not, and Google’s actual evaluation of a link is understood to weigh relevance and context alongside authority, factors a single composite score doesn’t capture. If the resulting page later outranks a competitor that acquired several links from sites similar to Site A, that outcome wouldn’t be surprising under how Google has described its own evaluation, even though it would look counterintuitive to a team screening prospects by DA/DR score alone.
