Domain Authority Explained: What It Is, How It Works, and How to Improve It

Domain Authority is one of the most referenced metrics in SEO — yet it is also one of the most misunderstood. Whether you are a business owner, a content marketer, or an SEO professional, knowing exactly what domain authority means, how it is calculated, what a good score looks like, and how it genuinely impacts your ability to rank on Google is essential to building a sustainable search strategy. This comprehensive guide answers every question you have about domain authority and gives you actionable steps to improve it.

---

What Is Domain Authority?

Domain Authority (DA) is a predictive SEO metric developed by Moz that scores a website on a scale of 1 to 100. The score estimates how competitive a domain is and how likely it is to rank highly in search engine results pages (SERPs). A domain authority score of 1 is the lowest possible, while a score of 100 represents the maximum strength — achieved only by the most powerful websites on the internet, such as Google, Wikipedia, and YouTube.

It is critical to understand that domain authority is not a metric used by Google itself. Google has its own internal algorithms for ranking websites, and domain authority does not directly influence those algorithms. Instead, domain authority is a third-party proxy metric that correlates with ranking ability based on observable data — primarily your backlink profile and the quality of domains linking to your site.

Think of domain authority as a competitive benchmark: a way of gauging your website’s strength relative to other domains competing for the same keywords. The higher your domain authority compared to a competitor’s, the more likely you are to outrank them — all other factors being equal.

The History and Development of Domain Authority

Moz introduced domain authority as part of its mission to help webmasters measure and understand SEO performance. When the metric first launched, backlink volume was the primary driver of scores. Over time, Moz refined its algorithm to incorporate link quality, contextual relevance, and the authority of linking domains, reflecting how search engines had evolved to value quality over quantity.

In 2019, Moz released Domain Authority 2.0, a significantly upgraded version of the scoring model that uses machine learning and incorporates spam detection to better reflect real-world ranking potential. This update made the metric more resilient to manipulation through link schemes and artificial link building.

Because the model continues to evolve, a domain’s authority score may fluctuate over time — even without any change to that domain — simply because the entire scoring model recalibrates as Moz’s web index grows and updates.

---

How Is Domain Authority Calculated?

Domain authority is calculated using a machine-learning algorithm developed by Moz that processes dozens of signals from your website’s link profile and cross-references them against known ranking data. The score is expressed on a logarithmic scale, which means it becomes progressively harder to improve as you climb higher. Moving from a DA of 20 to 30 is far easier than moving from 70 to 80.

Key Metrics That Determine Your Domain Authority Score

• Linking Root Domains: The number of unique external domains that link to your website. A single high-quality domain linking to you provides more value than hundreds of links from a single low-authority domain. Diversity of referring domains is one of the single strongest signals in the DA algorithm.
• Total Number of Backlinks: The overall count of inbound links — both from unique domains and repeat links from the same domain.
• MozRank and MozTrust: Moz’s own internal link popularity scores, which factor in the quality and trustworthiness of the linking pages.
• Domain Age: Older, established domains tend to accumulate more natural backlinks over time, which generally results in higher authority scores.
• Link Quality Over Quantity: Links from high-authority, topically relevant domains are exponentially more valuable than links from low-authority or unrelated sites.
• Spam Score: Sites with high proportions of spammy or toxic backlinks receive algorithmic penalties in their domain authority score. Maintaining a clean link profile is essential.
• Content Quality and Site Structure: While domain authority is primarily a link-based metric, well-structured sites that attract natural links and have strong topical coverage accumulate authority faster over time.

Why Domain Authority Uses a Logarithmic Scale

The logarithmic nature of the domain authority scale is intentional and important to understand. It means that the difference between a DA 10 and DA 20 site is much smaller than the difference between a DA 70 and DA 80 site. This mirrors the actual distribution of link equity across the web, where a small number of extremely powerful domains (think major news outlets, government sites, universities) hold a disproportionate share of link authority.

For most small-to-medium businesses, realistically targeting a domain authority of 30 to 50 is achievable and can be sufficient to outrank competitors in their niche — especially if those competitors have similarly modest scores.

---

What Is a Good Domain Authority Score?

One of the most common questions about domain authority is: what score should I be aiming for? The answer is entirely relative — a good domain authority score depends on your niche and your competition, not on an abstract absolute number.

The most important takeaway: always evaluate your domain authority relative to the domains you are actually competing against. A DA of 35 may be more than sufficient to rank on page one for a local plumbing keyword, while a DA of 60 might not be enough to compete in a saturated national market. Use domain authority as a competitive indicator, not a vanity metric.

---

How Domain Authority Impacts SEO Performance

While domain authority is not a direct Google ranking factor, there is a strong correlation between higher domain authority and better organic search rankings. This is because the same factors that drive domain authority — primarily high-quality backlinks from reputable domains — are also factors that Google’s algorithm weighs heavily when determining rankings.

Domain Authority and Keyword Ranking Potential

Sites with higher domain authority tend to rank for a broader range of keywords and can often rank for competitive terms with less individual page optimization. This is because Google’s algorithm considers the overall trust and authority of the domain when evaluating individual pages — a concept often called “domain-level trust” flowing to individual pages.

Conversely, sites with low domain authority often struggle to rank even with excellent on-page SEO, particularly in competitive niches. This is why link building is a non-negotiable component of any serious long-term SEO strategy.

Using Domain Authority for Competitive Analysis

Domain authority is most powerful as a competitive intelligence tool. Before targeting a keyword, check the domain authority scores of the websites currently ranking on page one. If the average DA of page-one results is 60+ and your site is at DA 25, you face a significant uphill battle. This insight helps you:

• Identify keyword opportunities where lower-DA sites are ranking, signaling openings you can exploit
• Set realistic expectations for how long it will take to rank for certain terms
• Prioritize link building targets by identifying which competitor backlinks to pursue
• Spot content gaps in competitor strategies where low-DA sites are outranking higher-authority domains, signaling that on-page relevance can overcome authority deficits in some cases

Monitoring your competitors’ domain authority regularly also reveals when they are aggressively building links — a signal that you may need to accelerate your own efforts to maintain competitive positioning.

---

Domain Authority vs. Page Authority: Understanding the Difference

Moz offers two closely related but distinct metrics: Domain Authority (DA) and Page Authority (PA). Understanding when to use each is essential for an effective SEO strategy.

When to use Domain Authority: Use DA when making strategic decisions about your overall website — whether to pursue a niche, how your brand stacks up against competitors, and whether your link-building strategy is working at a domain level over time.

When to use Page Authority: Use PA when you want to evaluate the competitive strength of a specific URL — for example, when deciding whether your blog post can outrank a competitor’s article for a target keyword, or when identifying which of your own pages to build more links toward.

The most effective SEO strategies use both metrics together: DA provides the macro view, while PA provides the micro view needed for page-level content and link-building decisions.

---

Domain Authority vs. Domain Rating: What’s the Difference?

A frequent source of confusion is the difference between Domain Authority (DA), which is Moz’s metric, and Domain Rating (DR), which is Ahrefs’ equivalent metric. Both measure the strength of a domain’s backlink profile, but they use different methodologies and are not interchangeable.

• Domain Authority (Moz DA): Based on Moz’s web index. Uses a machine-learning model trained on Google search results. Ranges from 1–100.
• Domain Rating (Ahrefs DR): Based on Ahrefs’ own backlink index — one of the largest in the industry. Also ranges from 0–100 but uses a different logarithmic weighting system focused on the quantity and quality of unique referring domains.
• URL Rating (Ahrefs UR): Ahrefs’ equivalent of Moz’s Page Authority — measures the link strength of an individual URL.

A site may have a DA of 45 and a DR of 52, or vice versa — this does not indicate a problem. It simply reflects differences in each tool’s web crawl coverage and scoring methodology. For a complete picture, using both tools in tandem is the recommended best practice among advanced SEO professionals.

---

How to Improve Your Domain Authority: A Step-by-Step Strategy

Improving your domain authority is a long-term investment, not a quick fix. The following strategies are the most evidence-backed approaches to sustainably increasing your DA score over time.

1. Build High-Quality Backlinks from Authoritative Domains

The single most impactful action you can take to raise your domain authority is earning backlinks from high-authority, topically relevant domains. A single link from a DA 80 domain in your industry is worth more than 500 links from DA 10 sites. Effective link-building tactics include:

1. Digital PR and data-driven content: Create original research, surveys, or industry reports that journalists and bloggers want to cite.
2. Guest posting on industry publications: Write expert content for authoritative websites in your niche in exchange for a contextual backlink.
3. Broken link building: Find broken links on authoritative sites and offer your relevant content as a replacement.
4. Skyscraper technique: Identify high-performing competitor content, create a definitively better version, and reach out to sites linking to the original.
5. Resource page link building: Get your content listed on curated resource pages in your industry.
6. HARO (Help A Reporter Out): Respond to journalist queries to earn media mentions and backlinks from high-authority news sites.

2. Audit and Disavow Toxic Backlinks

Low-quality, spammy, or toxic backlinks can actively drag down your domain authority and trigger Google penalties. Conduct a thorough backlink audit using tools like Moz, Ahrefs, or SEMrush to identify harmful links. Once identified, reach out to the linking domains and request removal. For links that cannot be removed, use Google’s Disavow Tool to instruct Google to ignore them. A clean backlink profile is foundational to a healthy domain authority score.

3. Create Consistently Linkable, High-Quality Content

Content that earns backlinks naturally is your most scalable link-building asset. Focus on creating:

• Ultimate guides and comprehensive resources that become the definitive reference in your niche
• Original data, statistics, and research that others will cite
• Infographics and visual assets that publishers embed with a link back to your site
• Expert opinion pieces and thought leadership content that builds topical authority
• Freshly updated evergreen content that maintains relevance and continues to attract links over time

4. Strengthen Your Internal Linking Structure

Internal linking passes authority throughout your site, helping distribute link equity from your highest-authority pages to your newer or weaker pages. Audit your site for orphaned pages (pages with no internal links pointing to them) and ensure every important page is accessible within three clicks from your homepage. Use descriptive, keyword-rich anchor text for internal links to reinforce topical relevance signals.

5. Optimize Technical SEO to Support Authority Growth

Technical SEO does not directly calculate into your domain authority score, but it supports the conditions that allow authority to grow. Key technical SEO factors to address include:

• Page load speed: Fast-loading pages improve user experience and reduce bounce rates, keeping visitors engaged with your content
• Mobile responsiveness: Google uses mobile-first indexing, meaning your mobile experience directly influences rankings
• HTTPS security: Secure sites are trusted by both users and search engines; an SSL certificate is a baseline requirement
• Crawlability and indexability: Ensure search engines can efficiently crawl and index all of your important pages
• Fixing broken links (404 errors): Broken internal and external links waste crawl budget and create a poor user experience
• Structured data markup: Schema markup helps search engines understand your content, improving how your pages appear in SERPs

6. Increase Referring Domain Diversity

Ten links from ten different domains are worth significantly more to your domain authority than ten links from the same domain. Focus your outreach on acquiring backlinks from a diverse range of unique referring domains rather than getting multiple links from a single source. Diversity of linking domains is one of the most reliable indicators of organic, earned authority — the kind that both Moz’s algorithm and Google’s algorithm reward most heavily.

---

Common Domain Authority Mistakes to Avoid

Understanding what to do is only half the equation. Avoiding these common mistakes is equally important for protecting and growing your domain authority.

• Buying links from link farms or PBNs: Purchased links from private blog networks or link farms violate Google’s guidelines and can tank your domain authority and organic rankings when discovered.
• Chasing DA as a vanity metric: Obsessing over your DA number in isolation, without comparing it to your actual competitors, leads to misdirected effort and wasted resources.
• Ignoring link quality for link quantity: Acquiring hundreds of low-quality links provides negligible benefit and increases your spam score, potentially harming your DA.
• Publishing thin or duplicate content: Thin content earns no links, signals low editorial quality, and reduces the overall authority of your domain.
• Neglecting technical SEO issues: Crawl errors, slow page speeds, and broken links impair your site’s performance in ways that indirectly limit authority growth.
• Expecting overnight results: Domain authority is a lagging indicator. Meaningful score changes can take weeks to months to materialize after implementing link-building campaigns.
• Confusing DA with Google’s actual ranking factors: Domain authority is a predictive metric, not a Google signal. Focus on the underlying factors (quality links, great content, strong UX) rather than gaming the DA score itself.

---

Best Tools to Check and Track Domain Authority

Knowing which tools to use — and how to interpret what they tell you — is essential for making domain authority data actionable in your SEO strategy.

Moz Link Explorer

The original home of domain authority. Moz’s Link Explorer provides your DA score, Page Authority scores, linking root domains, total backlinks, and a spam score. You can also use it to analyze competitor backlink profiles and track your DA over time. A free account provides limited monthly lookups; a Moz Pro subscription unlocks full access.

Ahrefs Site Explorer

Ahrefs offers Domain Rating (DR) as its equivalent to DA, backed by one of the web’s largest backlink indexes. Site Explorer provides comprehensive backlink data, referring domain analysis, organic keyword rankings, and content gap analysis. Particularly strong for identifying link-building opportunities and performing competitive backlink research.

SEMrush Authority Score

SEMrush provides its own “Authority Score” metric (similar in concept to DA) alongside a comprehensive suite of backlink analysis, keyword ranking, and site audit tools. SEMrush is particularly effective for combining domain authority analysis with keyword research and content strategy planning in a single platform.

Moz Bar (Free Chrome Extension)

For quick on-the-fly domain authority checks while browsing, the free MozBar Chrome extension displays DA and PA scores directly in your browser for any website you visit — including SERP results. An excellent tool for rapid competitive analysis while doing keyword research.

How to Interpret Your Domain Authority Results

When reviewing your DA score, avoid looking at it in isolation. Always benchmark it against:

• The DA scores of the top 5–10 ranking pages for your target keywords
• The DA scores of your direct competitors in your niche
• Your own historical DA trend over the past 6–12 months to assess whether your link-building efforts are working

A rising DA trend over time — even by modest increments — is a strong positive indicator that your SEO strategy is building lasting authority. A declining DA trend warrants investigation into toxic backlinks or a weakening link profile relative to the broader web.

---

How Long Does It Take to Improve Domain Authority?

This is one of the most practical questions SEOs and business owners ask, and the honest answer is: it depends on your starting point, your niche, and the aggressiveness of your link-building efforts.

• New domains (DA 1–15): With consistent content publishing and targeted link building, you can expect to reach DA 20–30 within 6 to 12 months.
• Growing domains (DA 15–35): Moving through this range with a focused backlink acquisition strategy typically takes 12 to 24 months of sustained effort.
• Established domains (DA 35–60): Progress slows due to the logarithmic scale. Meaningful gains at this level require high-authority link acquisition and may take 2 to 4 years.
• High-authority domains (DA 60+): At this level, maintaining and incrementally growing DA requires consistent earned media coverage, substantial content investment, and ongoing technical SEO maintenance.

Domain authority scores are also recalculated periodically by Moz as its index is updated. You may see fluctuations that do not reflect actual changes to your link profile — this is normal. Focus on the long-term trend, not month-to-month variance.

---

Frequently Asked Questions About Domain Authority

---

Key Takeaways: What You Need to Know About Domain Authority

• Domain authority is a Moz metric, not a Google ranking factor — but the factors that drive DA also drive Google rankings, making it a useful proxy for SEO health.
• Scores range from 1 to 100 on a logarithmic scale — higher scores are increasingly harder to achieve and gains slow as you climb.
• What matters is your DA relative to your competitors, not an absolute number in isolation.
• The biggest driver of domain authority is earning quality backlinks from diverse, authoritative, and topically relevant domains.
• Improving DA is a long-term process — meaningful gains typically take 6 months to 2+ years depending on your starting point and investment level.
• Use both Domain Authority and Page Authority for a complete picture of your SEO positioning at the domain level and page level.
• Avoid shortcuts like buying links — these can increase your spam score and harm your rankings with Google even if they temporarily inflate a DA score.
• Track DA trends over time, not just point-in-time scores, to measure the effectiveness of your SEO efforts.