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Domain authority

Domain authority is a third-party score estimating a website's strength in search from the links pointing to it; widely used versions include Moz's Domain Authority (DA) and Ahrefs' Domain Rating (DR).

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Also called DA · domain rating · DR

Domain authority, explained

Both are 100-point scales computed from each company's own link index. Ahrefs describes DR as the strength of a site's backlink profile compared with others in its database; Moz presents DA as a prediction of how well a site will rank. Both scores are made by third-party companies, not by Google, and each company calculates its score with its own method.

For a domain investor, these scores are a quick filter when screening expired and aged names, nothing more. They can be inflated with paid or spammy links, they say nothing about trademark risk or brand value, and an end user buying a name to build a company rarely cares about them. The common mistake is paying extra for a high DA or DR without checking the referring domains behind it. Sell a name on its words and its buyers, not on a third-party score.

Example. An expired .com shows a high DR, but its referring domains are mostly link farms, so the investor values it as a plain name and ignores the score.

Go deeper Expired Domains and Drop Catching: How the Domain Lifecycle Works

Sources

  1. Ahrefs Help Center — What is Domain Rating (DR)? (accessed Oct 1, 2026)
  2. Wikipedia — Domain authority, Moz's Domain Authority metric (accessed Oct 1, 2026)

Education, not financial, legal or tax advice. Domain investing is speculative and most domain names never sell. Read the disclaimer.

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