Domain authority isn't a single official metric—it's a predictive score created by SEO tools to estimate how well a site might rank. Moz's DA is the original, scaled 0–100, but Ahrefs DR and Semrush Authority Score serve the same purpose. You check DA by entering a domain into Moz Link Explorer, which gives you a free lookup with limited daily checks. Paid Moz plans start around $99 USD/month for unlimited checks and historical data. Ahrefs DR is arguably more reliable because Ahrefs has the second-largest crawl budget after Google, so their backlink index is fresher. DR also runs 0–100. A free Ahrefs Webmaster Tools account lets you check your own sites; otherwise you need a paid plan starting around $129 USD/month. Semrush Authority Score factors in traffic data and organic visibility alongside backlinks, making it slightly more holistic but also less portable when discussing authority with other SEO practitioners. At Ottawa SEO, we primarily use Ahrefs DR for internal analysis because the backlink data updates faster and the interface is cleaner for portfolio-scale checks across 500+ domains. When a client asks about DA, we explain that a DA 30 site in a niche vertical can outrank a DA 50 generalist site for specific queries—authority is relative to the competitive set, not absolute. A local Ottawa law firm with DA 25 and 40 high-quality local citations will beat a DA 35 blog with spammy links every time. Practical thresholds: DA/DR under 20 is typical for new sites or thin domains. 20–40 is established with decent backlinks. 40–60 is competitive. Above 60 you're looking at major publications or well-linked brands. Don't obsess over moving from DA 32 to DA 34—focus on acquiring links from domains with higher authority than yours, relevant to your niche. The score will follow. Check quarterly, not weekly, because meaningful authority shifts take months of sustained link building. How to Check Website Domain Authority Using Free Tools Most practitioners need quick spot-checks rather than full-suite subscriptions. MozBar, the free Chrome extension, displays DA directly in search results and on any page you visit—useful for competitive scoping without leaving your browser. Ubersuggest offers free domain authority lookups with three checks daily before requiring a login. SmallSEOTools and Website Authority Checker aggregate data from multiple sources, though their scores often lag behind Moz by several weeks. For agencies evaluating prospects or freelancers vetting potential clients, these free domain authority checker options handle one-off lookups without subscription overhead. The tradeoff is data freshness: paid tools update backlink indexes weekly or faster, while free alternatives may reflect link profiles from 30-60 days prior. For competitive analysis where timing matters, paid tools justify their cost. Where to Check DA of a Site for Competitor Research When building a competitive link gap analysis, knowing where to check DA of a site efficiently matters. Start with Moz Link Explorer's free tier—enter a competitor URL and note their DA alongside linking domains count. Then cross-reference with Ahrefs' free backlink checker, which shows DR plus the top 100 backlinks. This dual-check approach catches discrepancies: a site might show DA 45 but DR 28 because Moz weighs spam links differently than Ahrefs. For client presentations, we typically pull both metrics and explain the variance. Bulk checking via spreadsheet imports is where paid plans become essential—Moz Pro and Ahrefs both accept CSV uploads for checking hundreds of domains in minutes. Export those results, sort by authority, and you have a prioritized outreach target list based on realistic link acquisition difficulty. How to Find Domain Authority Score for Your Own Website Finding your own domain authority score requires connecting your site to the tool's index. In Moz Link Explorer, simply enter your root domain—no verification needed for basic DA lookup. For deeper data including page-level authority and spam score, claim your site in Moz Pro. Ahrefs Webmaster Tools is genuinely free for verified site owners: add your domain via DNS or HTML file, and you get full DR data plus complete backlink profile access without paying. Google Search Console verification usually transfers, speeding setup. Check your authority score monthly and track it in a simple spreadsheet alongside key metrics like referring domains count and organic traffic. Authority scores fluctuate when tools recalibrate their indexes—a two-point drop without losing links usually means index-wide rescoring, not a penalty. Focus on referring domain growth rate rather than absolute score. Interpreting Domain Authority Scores Across Different Tools Tool scores aren't interchangeable, which confuses teams new to authority metrics. A domain showing DA 40 in Moz might register DR 52 in Ahrefs and Authority Score 38 in Semrush—all measuring the same site. This happens because each tool weights backlink factors differently: Moz emphasizes link equity distribution, Ahrefs prioritizes raw link velocity and dofollow ratios, Semrush incorporates traffic signals. Pick one tool as your baseline and use it consistently for tracking and reporting. Mixing metrics across tools creates false trend narratives. When reporting to stakeholders unfamiliar with SEO, explain that these scores predict ranking potential rather than measure actual Google rankings—Google doesn't use third-party DA scores in their algorithm. The value is benchmarking against competitors using identical methodology, not treating the number as an objective truth. Frequently Asked Questions How to check website domain authority? Enter any URL into Moz Link Explorer, Ahrefs Site Explorer, or Semrush Domain Overview. Each displays their proprietary authority score instantly. For quick checks without logging in, use MozBar browser extension or free tools like Ubersuggest and SmallSEOTools. What is the best free domain authority checker? MozBar Chrome extension provides free DA checks on any site you visit. Ahrefs Webmaster Tools offers free DR data for sites you own. Ubersuggest allows three free daily lookups. For bulk checking, free options are limited—paid tools become necessary. How to find domain authority score without paying? Use Moz Link Explorer's free tier for 10 monthly queries, MozBar extension for unlimited basic lookups, or verify your site in Ahrefs Webmaster Tools for complete free access to your own domain's metrics including DR and full backlink data. Where to check DA of a site quickly? MozBar extension shows DA directly in Google search results next to each listing. For individual lookups, Moz Link Explorer and Ahrefs free backlink checker both return scores within seconds of entering a domain.