Domain Authority (DA) is not a Google metric — it is Moz's modelled estimate based on the domain's link profile. It is useful for comparing domains within the same industry but should never be treated as a direct ranking factor.
How it is calculated
DA is computed from the number and quality of referring domains, the strength of the linking pages, and the diversity of the link profile, then normalised so higher scores are exponentially harder to achieve.
Example
A three-year-old B2B blog with a DA of 42 outranks a five-year-old competitor with a DA of 38 on shared queries — but a DA of 90 does not guarantee any specific ranking on a specific query.
How SEM Optimiser reports it
DA is displayed with a clear "Moz" attribution and never mixed with Ahrefs Domain Rating in the same comparison chart.
Related terms
- Domain Rating
Domain Rating is a proprietary Ahrefs metric on a 0-to-100 scale that measures the strength of a domain's backlink profile.
- Backlink
A backlink is a hyperlink on an external website that points to a page on your own domain, and is one of the strongest ranking signals in Google's algorithm.
- Referring Domain
A referring domain is a unique external website that links to your site at least once, regardless of how many individual backlinks originate from it.