Definition
Authority (Domain Authority / Domain Rating) - A third-party metric (not Google's) estimating a site's overall link strength. Moz calls it Domain Authority (DA); Ahrefs calls it Domain Rating (DR). Higher scores generally correlate with better ranking potential, but they're proxies - not ranking factors themselves.
In more depth
Domain Authority (DA) and Domain Rating (DR) are metrics invented by Moz and Ahrefs respectively to give a single-number approximation of a site's link strength. They're calculated from the quantity and quality of inbound links and typically score sites on a logarithmic scale from 0 to 100. A jump from DR 20 to DR 40 is much harder than a jump from DR 0 to DR 20.
The crucial caveat: these are third-party proxies, not Google ranking factors. Google does not use DA or DR. What Google uses is its own internal assessment of PageRank and relevance - and while high DA/DR sites often rank well, the correlation is imperfect. A niche DR 25 site can absolutely outrank a DR 70 site on specific queries where it has more topical authority and relevance.
For link building strategy, DR/DA is useful as a quick quality filter - you generally want links from sites with higher scores than yours, in relevant niches. But don't reject a link opportunity purely because a site has low DR; a highly relevant, engaged audience can be more valuable than a high-DR site with no topical connection to yours.
Related terms: Backlink - Link Building - PageRank
Frequently asked questions
Is Domain Authority a Google ranking factor?
No. Domain Authority and Domain Rating are proprietary third-party metrics created by Moz and Ahrefs. Google does not use either in its algorithm. They're useful proxies but should not be treated as authoritative measures of ranking potential.
How do I increase my Domain Rating?
DR increases when you earn links from websites with higher DR than yours, from a diverse range of domains, in relevant niches. The most effective tactics: digital PR, original research, expert citations, and building genuinely useful tools or resources that others link to naturally.
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