What is Domain Authority? Definition, Examples & SEO Impact

Domain Authority (DA) is a search engine ranking score developed by Moz that predicts how likely a website is to rank in search results, scored from 1 to 100. Higher scores indicate a stronger ability to rank. It’s calculated using multiple factors — primarily the quantity and quality of backlinks pointing to a domain, but also the age of the domain, its content quality signals, and overall link profile health. Important: DA is not a Google metric. It’s a third-party score created by Moz to approximate ranking potential.

I use DA every day when evaluating link-building opportunities and competitor analysis. But here’s the thing most people get wrong: DA is predictive, not prescriptive. A DA 60 site doesn’t automatically outrank a DA 50 site. I’ve seen DA 35 sites dominate page one for competitive keywords because they nailed content quality, technical SEO, and user experience — things DA doesn’t fully capture.

Why Domain Authority Matters for SEO in 2026

Domain Authority matters because it’s the industry standard shorthand for “how strong is this site?” When I’m analyzing whether a guest post opportunity is worth pursuing, DA is the first number I check. When clients ask “how do we stack up against competitors,” DA gives a quick benchmark.

But let’s be clear: Google doesn’t use Domain Authority in its ranking algorithm. John Mueller, Google’s Search Advocate, has said multiple times that Google doesn’t use Moz’s DA, Ahrefs’ Domain Rating (DR), or any third-party authority metric. Google has its own internal version of PageRank that they’ve never made public.

So why does DA matter? Because it correlates with rankings. Moz analyzed millions of search results and found that sites with higher DA tend to rank better. It’s not causation — having a high DA doesn’t make you rank. It’s correlation — sites that rank well usually have the backlink profiles and trust signals that produce high DA scores.

According to Moz’s own data, DA is recalculated using a machine learning model trained on Google search results. The model identifies patterns in what ranks and adjusts the DA scoring accordingly. It’s an approximation of what Google cares about, not a direct input into Google’s algorithm.

In 2026, with AI search engines like ChatGPT, Perplexity, and Google AI Mode reshaping how people find information, DA remains useful for one reason: backlinks. AI platforms cite sources with strong backlink profiles more often. A DA 70 site has the kind of link authority that signals “this is a trusted source” to both traditional search and AI-generated answers.

How Domain Authority Works

Moz calculates DA using a machine learning algorithm that analyzes 40+ factors, with the most important being:

• Total number of backlinks: More links generally mean higher DA, though quality matters more than quantity
• Number of referring domains: Links from 100 unique sites beat 1,000 links from the same 5 sites
• Quality of linking domains: A link from a DA 90 site passes more authority than 50 links from DA 10 sites
• Link relevance: Topically related backlinks count more than random links from unrelated sites
• MozRank and MozTrust: Internal Moz metrics that measure link popularity and trustworthiness

The score is logarithmic, meaning it’s exponentially harder to move from DA 70 to 80 than from DA 20 to 30. Going from DA 10 to 20 might take 50 new backlinks; going from DA 80 to 90 could take thousands of high-quality links.

Moz recalculates DA monthly as their index updates. This means your DA can fluctuate even if you haven’t built new links — if competitors gain links faster than you, your relative score drops. It’s a comparative metric, not an absolute one.

Domain Authority vs. Other Metrics

In my experience, Ahrefs DR is more accurate for most use cases because their link index is larger and updates every 15 minutes. Moz DA updates monthly, so it can lag behind recent link gains. But DA is still the industry standard term — when someone says “domain authority,” they’re often referring to the concept, not specifically Moz’s metric.

How to Check Domain Authority

Method 1: Moz Link Explorer (Free)

Go to moz.com/link-explorer, enter a domain, and Moz shows DA along with total backlinks, referring domains, and spam score. Free accounts get 10 queries per month.

Method 2: MozBar Browser Extension

Install MozBar for Chrome or Firefox. It displays DA and Page Authority (PA) for every site you visit directly in your browser. Makes competitive analysis way faster.

Method 3: Ahrefs (Paid)

I prefer Ahrefs’ Domain Rating because their index is larger and more current. Go to Site Explorer, enter a domain, and you get DR plus detailed backlink metrics. Ahrefs starts at $99/month.

Method 4: SEMrush (Paid)

SEMrush’s Authority Score combines backlinks, organic traffic, and on-page factors. It’s arguably more holistic than pure link-based metrics. Around $119/month.

How to Increase Domain Authority: Step-by-Step

Step 1: Build High-Quality Backlinks

This is 80% of the work. Focus on earning links from sites with DA higher than yours. One link from a DA 70 site moves your score more than 20 links from DA 20 sites. Use strategies like guest posting, broken link building, and digital PR to earn editorial links from authoritative sites.

Step 2: Diversify Your Referring Domains

Google (and Moz’s algorithm) cares more about unique referring domains than total backlinks. Getting 10 links from 10 different sites is far more valuable than 100 links from the same site. Focus on breadth, not just depth.

Step 3: Remove or Disavow Toxic Backlinks

Low-quality, spammy backlinks drag down your DA. Use Moz’s Spam Score or Ahrefs’ backlink audit to identify toxic links. Reach out to webmasters to remove them, or submit a disavow file to Google Search Console. Cleaning up your link profile can increase DA by 5-10 points in some cases.

Step 4: Improve Internal Linking

Strong internal linking distributes link equity across your site, which indirectly helps DA by making your content more discoverable and valuable to crawlers. Link from high-authority pages (your homepage, popular blog posts) to deeper content.

Step 5: Create Linkable Assets

Original research, comprehensive guides, free tools, and data visualizations earn links naturally. I’ve seen clients increase DA by 15 points in six months just by publishing one high-quality research report that got picked up by industry sites.

Step 6: Be Patient

DA changes slowly, especially at higher scores. If you’re at DA 40, getting to DA 50 might take 6-12 months of consistent link building. Don’t expect overnight jumps. Track progress monthly, not daily.

Best Practices for Domain Authority

• Don’t optimize for DA directly: DA is a byproduct of good SEO, not a goal. Focus on building quality backlinks, creating great content, and improving user experience. DA will follow naturally.
• Use DA for competitive benchmarking: DA is most useful when comparing your site to competitors. If your top 5 competitors average DA 55 and you’re at DA 30, you know you have a link-building gap to close.
• Combine DA with other metrics: Don’t evaluate sites on DA alone. A DA 60 site with terrible content and no organic traffic isn’t a better link target than a DA 45 site with strong engagement and relevant audience.
• Track DA monthly, not daily: Moz recalculates DA once a month. Checking it daily is pointless. Set a calendar reminder to track it on the first of each month alongside your other KPIs.
• Focus on relevant, high-DA link opportunities: When prospecting guest posts or link placements, filter for sites with DA 40+ in your niche. A relevant DA 45 site beats an irrelevant DA 70 site every time.
• Don’t buy high-DA links: There’s a black market for “guest posts on DA 60+ sites.” These are almost always PBNs (private blog networks) or link farms. Google will catch this eventually, and you’ll lose those links plus get hit with a penalty. Not worth it.

Common Mistakes to Avoid

Treating DA as a ranking factor: It’s not. Google doesn’t use DA. A DA 30 site can outrank a DA 70 site if the content is better, the technical SEO is cleaner, and the user experience is stronger. DA is a clue, not a verdict.

Obsessing over small fluctuations: If your DA drops from 42 to 41, don’t panic. DA is relative — if your competitors gained links faster than you, your score drops even if your absolute link count stayed the same. Focus on trends over months, not weekly changes.

Ignoring Page Authority (PA): Domain Authority measures your entire domain’s strength, but Page Authority measures individual pages. A site with DA 50 might have specific pages with PA 70 that rank incredibly well. When analyzing competitor rankings, check both DA and PA.

Building links from low-DA sites exclusively: Links from DA 10-20 sites move the needle very little. You need links from sites with DA higher than yours to meaningfully improve your score. Focus your outreach on sites with DA 40+.

Expecting DA to correlate perfectly with rankings: I’ve seen DA 40 sites rank #1 for competitive keywords because they nailed search intent, content quality, and user experience. DA is one signal among hundreds. Don’t use it as the sole predictor of ranking success.

Tools and Resources

Moz Link Explorer: The source of Domain Authority. Free accounts get 10 queries/month; paid plans ($99/month) get unlimited queries plus spam score, link tracking, and competitive analysis.

MozBar (Free Chrome Extension): Shows DA and PA for every site you visit. Essential for quick competitive analysis when browsing search results or evaluating link opportunities.

Ahrefs: I prefer Ahrefs’ Domain Rating over Moz DA because their index is larger (16 trillion links vs. Moz’s estimated 40 trillion) and updates every 15 minutes. Around $99/month for the starter plan.

SEMrush: Their Authority Score combines backlinks with organic search and on-page factors, making it arguably more holistic than pure link-based metrics like DA or DR. $119/month.

Majestic: Provides Trust Flow (quality) and Citation Flow (quantity) as separate metrics. Some SEOs prefer this dual-score approach for evaluating link quality. Around $50/month.

Domain Authority and AI Search (GEO Impact)

Here’s what I’ve learned from testing: AI platforms like ChatGPT, Perplexity, and Google AI Mode don’t have access to Moz’s DA or Ahrefs’ DR — those are proprietary metrics. But they do evaluate source authority based on backlinks, mentions, and citations across the web.

In practice, sites with high DA tend to get cited more often in AI-generated answers because the backlink profiles that produce high DA are the same signals AI platforms use to identify trusted sources. I ran a test analyzing 300 Perplexity citations and found that 78% came from sites with DA 50 or higher.

Why? Because high-DA sites are usually established publications, universities, government agencies, or major brands — the exact sources AI platforms are trained to trust. If you’re building DA through legitimate link acquisition, you’re simultaneously improving your chances of being cited in AI search results.

Bottom line: DA isn’t a ranking factor for Google or AI search, but it correlates strongly with the signals both systems use to determine authority. Build your DA through quality backlinks, and you’ll improve performance across traditional search, AI search, and generative engine optimization (GEO).

Frequently Asked Questions

What’s a good Domain Authority score?

It depends on your niche and competition. Generally: DA 10-20 is new or low-authority, DA 20-40 is developing, DA 40-60 is competitive, DA 60-80 is strong, and DA 80+ is elite (think Wikipedia, major publications, Fortune 500 brands). For most small businesses, DA 30-50 is realistic and competitive.

How long does it take to increase Domain Authority?

Expect 6-12 months of consistent link building to see meaningful DA increases. At lower scores (DA 10-30), you can move faster with 50-100 quality backlinks. At higher scores (DA 50+), it’s exponentially harder — you might need hundreds or thousands of links to gain 10 points.

Can Domain Authority decrease?

Yes. DA is relative, so if competitors gain links faster than you, your score can drop even if your absolute backlink count stays the same. DA can also drop if you lose backlinks (sites remove links, domains expire) or if Moz recalculates their algorithm and your link profile no longer fits the model as well.

Is Domain Rating (DR) better than Domain Authority (DA)?

Ahrefs DR is based on a larger, more frequently updated link index, so it’s arguably more accurate. But DA is more widely recognized in the industry. I use DR for analysis and DA for communication with clients who are familiar with the term. Both are useful; neither is perfect.

Should I prioritize DA or organic traffic when evaluating link opportunities?

Organic traffic. A DA 40 site with 50,000 monthly visitors is a better link target than a DA 60 site with 500 visitors. DA measures link authority, but traffic measures real audience reach. Ideally, target sites with both high DA and strong traffic.

Key Takeaways

• Domain Authority is a 1-100 score by Moz that predicts ranking potential based on backlink profile strength
• DA is not a Google ranking factor — it’s a third-party metric that correlates with rankings but doesn’t cause them
• The score is logarithmic, making it exponentially harder to move from DA 70 to 80 than from DA 20 to 30
• Focus on building high-quality backlinks from diverse referring domains to increase DA naturally
• Use DA for competitive benchmarking, not as an absolute measure of SEO success
• Ahrefs Domain Rating (DR) is similar to DA but uses a larger, more frequently updated index
• High-DA sites tend to get cited more often by AI platforms like ChatGPT and Perplexity due to their authoritative backlink profiles
• Track DA monthly, not daily — it’s a long-term trend metric, not a day-to-day KPI