Domain Authority is a proprietary score developed by Moz that attempts to predict a website's ranking potential on a 1–100 scale. It's calculated using dozens of factors, primarily the quality and quantity of inbound links pointing to a domain. A site with DA 70 has significantly more ranking power than one with DA 30, though the scale is logarithmic—jumping from 40 to 50 is easier than 70 to 80. Google doesn't use Domain Authority in its algorithm. DA is a third-party approximation of what Google might consider important. That said, the signals DA measures—authoritative backlinks, link diversity, spam ratio—overlap heavily with what Google's algorithms do evaluate. When we analyze link prospects at Ottawa SEO, we look at DA alongside traffic estimates and topical relevance, not as gospel but as a quick filter. A DA 45 news site in your niche typically offers more value than a DA 60 generic directory. The practical implications: high-DA domains generally require better content and outreach to earn links from. A DA 80 publication like The Globe and Mail won't link to thin content, while a DA 25 local blog might. For link building, target a mix—some attainable DA 20–40 sites in your industry, occasional wins in the DA 50–70 range, and maybe one or two marquee DA 80+ placements per year if your content truly warrants it. Don't obsess over your own site's DA month-to-month. It updates irregularly and fluctuates as Moz recalibrates its index. Focus instead on acquiring quality links from relevant, trusted sources. Your DA will follow. We've seen client domains jump from DA 18 to DA 42 over 18 months purely through consistent digital PR and resource-page outreach, no manipulation required. Other metrics exist—Ahrefs Domain Rating, Semrush Authority Score—but they all attempt the same thing: quantifying domain strength based on backlinks. Use them as directional indicators, not ranking guarantees.