Domain Authority is not a Google ranking factor. It's a third-party metric developed by Moz, scored from 1 to 100, that attempts to predict how well a site might rank. Google's John Mueller has explicitly stated that Google does not use DA in its algorithm. Google doesn't even have access to Moz's proprietary data, so it couldn't use DA even if it wanted to. What Google does use are its own authority signals. PageRank still exists internally at Google, though it's far more sophisticated than the toolbar version they discontinued in 2016. Google evaluates link equity, topical authority, E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness), and hundreds of other signals. DA is simply Moz's attempt to reverse-engineer some of these signals into a single number. That said, DA isn't useless. It serves as a rough comparative benchmark when evaluating link prospects or competitors. If you're choosing between two potential backlink sources and one has DA 65 while the other has DA 25, the higher-DA site likely has stronger link profiles and more established authority—qualities Google does care about, even if it doesn't care about the DA number itself. At Ottawa SEO, we track DA in our portfolio analytics, but we never optimize for DA. We optimize for the underlying factors: earning links from relevant, trusted sources, building topical depth, and improving user signals. The confusion happens because DA often correlates with rankings. Sites with high DA tend to rank well, but that's because both DA and Google rankings respond to similar inputs—quality backlinks, content depth, site age, and trust signals. Correlation is not causation. Improving your DA by buying spammy links from high-DA sites won't help your Google rankings and will likely hurt them. Focus on what Google actually measures: relevant links, content quality, technical health, and user satisfaction. DA will rise as a side effect if you do those things right.