Glossary · Off-page
Domain authority
Definition. Domain authority is a third-party score, from Moz, Ahrefs, Semrush or another vendor, estimating how likely a domain is to rank based mainly on its backlink profile. No search engine uses these scores; they are vendor metrics for comparison.
They are useful for comparing two sites within the same tool and meaningless across tools, since each vendor's index and formula differ.
Google has repeatedly said it has no single site-wide authority score of this kind. Treat these numbers as a rough proxy for link strength, not as a target.
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Frequently asked questions
What does Domain authority mean?
Domain authority is a third-party score, from Moz, Ahrefs, Semrush or another vendor, estimating how likely a domain is to rank based mainly on its backlink profile. No search engine uses these scores; they are vendor metrics for comparison.
Why does Domain authority matter for AI SEO?
They are useful for comparing two sites within the same tool and meaningless across tools, since each vendor's index and formula differ.
What is the most common mistake with domain authority?
Google has repeatedly said it has no single site-wide authority score of this kind. Treat these numbers as a rough proxy for link strength, not as a target.
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