Domain Authority

Domain Authority (DA) is a metric created by Moz that predicts how likely a website is to rank in search engine results. It scores domains on a scale from 0 to 100, with higher scores corresponding to a greater likelihood of ranking. Ahrefs has a similar metric called Domain Rating (DR), and Semrush uses Authority Score. None of these are Google metrics. They are third-party approximations based on backlink analysis.

Why it matters: while DA is not a Google ranking factor, it serves as a useful proxy for competitive analysis. If your site has a DA of 35 and you are trying to rank against sites with DAs of 70-80, you will likely need significantly better content, more targeted keywords, and a focused link-building strategy. DA helps you set realistic expectations and choose battles you can win. It is also commonly used in link building to evaluate the quality of potential linking sites: a backlink from a DA 70 site is generally more valuable than one from a DA 15 site.

How it is calculated: Moz's DA is based primarily on the quantity and quality of backlinks pointing to a domain, using data from Moz's link index. The score is logarithmic, meaning it is much easier to go from 20 to 30 than from 70 to 80. A brand new site starts near 0, and only the largest, most linked-to sites (Google, Facebook, Wikipedia) reach the upper 90s.

How to improve it: the primary lever is earning high-quality backlinks from authoritative, relevant sites. Publish link-worthy content (original research, data studies, free tools, definitive guides). Remove or disavow toxic backlinks from spammy sites. Improve your site's technical SEO foundation (site speed, crawlability, internal linking). Build topical authority by publishing comprehensive content clusters around your core topics.

Common mistakes: obsessing over DA as a goal rather than a diagnostic tool. DA should rise as a byproduct of good SEO practices, not as a target in itself. Comparing DA across different tools (Moz DA, Ahrefs DR, Semrush AS use different scales and methodologies). Paying for links from "high DA" sites, which is a violation of Google's guidelines and often involves artificially inflated metrics. Ignoring that page-level authority matters as much as domain-level: a strong domain with a weak page may still lose to a weaker domain with a highly linked page.

Practical example: a B2B SaaS startup with a DA of 28 wants to rank for competitive terms where incumbents have DAs of 60+. Instead of targeting head terms like "project management software," they focus on long-tail keywords like "project management for remote design teams." They build topical authority through a content cluster of 15 interconnected articles, earn backlinks through guest posts and data studies, and within 12 months reach DA 42 while ranking on page one for their targeted long-tail terms.