Domain Authority (DA) is a Moz-specific metric, so the most direct place to find it is through Moz's own tools. Install the free MozBar Chrome or Firefox extension and it displays DA scores when you browse any website. For deeper analysis, use Moz's Link Explorer at moz.com/link-explorer, which gives you 10 free queries per month without an account and shows DA alongside page authority and backlink counts. If you work with link prospecting regularly, a paid Moz Pro subscription starts around $99 USD monthly and removes query limits. That said, DA is just one authority metric and many SEO practitioners prefer alternatives. Ahrefs uses Domain Rating (DR) on a 0-100 scale, calculated from their own backlink index, which tends to be larger and fresher than Moz's. Semrush offers Authority Score, which factors in backlink quality, organic search traffic, and other signals. Both require subscriptions starting at $99-129 USD monthly. At Ottawa SEO, we typically cross-reference multiple metrics rather than relying on DA alone. A site with DA 45 but spammy backlinks is worse for outreach than a DA 28 site with clean, relevant links. We pull DA from MozBar for quick checks, then verify link quality in Ahrefs before adding domains to our outreach lists for our portfolio sites. One thing to remember: DA updates roughly monthly, so if a site just earned strong links, the score lags. Also, DA is relative and logarithmic—jumping from 20 to 30 is easier than 60 to 70. For Canadian markets, a local news site might have DA 50-65, a national outlet like CBC sits around DA 92, and most small business sites range from DA 10-30. Don't chase DA scores blindly; a contextually relevant DA 22 blog in your niche often outperforms a generic DA 55 directory for actual ranking impact.