Domain Authority (DA) is a critical concept in search engine optimization (SEO) used to predict how well a website will rank on search engine results pages (SERPs). Developed by Moz, Domain Authority provides a numerical score ranging from 1 to 100. Understanding Domain Authority, how it is calculated, and how to improve it can significantly influence your website’s SEO strategy and success.

What Is Domain Authority in SEO?

Domain Authority is a search engine ranking score that estimates the likelihood of a website ranking in search results. It is not used by Google, but it is widely adopted by marketers and SEO professionals as a benchmark for comparing website strength. The higher your Domain Authority score, the more likely your site is to rank well on SERPs.

Who Created Domain Authority?

Domain Authority was created by Moz, a leading company in the SEO industry. Moz introduced the metric to help webmasters and marketers evaluate and compare the strength of different domains based on a variety of signals.

How Is Domain Authority Calculated?

Domain Authority is calculated using dozens of factors, including:

• Linking root domains – the number of unique websites linking to your site
• Total number of backlinks – the quantity and quality of inbound links
• MozRank and MozTrust – proprietary metrics based on link quality
• Site structure and internal linking
• Content relevance and consistency

These signals are processed through a machine learning model that compares your domain to others in Moz’s index. The model predicts how likely your site is to rank relative to the rest of the web.

What Is a Good Domain Authority?

There is no universally "good" Domain Authority score. DA is a comparative metric, meaning its value depends on the competition within your niche. However, as a general guideline:

• 1–20: Low authority (typically new or poorly optimized sites)
• 21–40: Fair authority
• 41–60: Good authority
• 61–80: Strong authority
• 81–100: Very high authority (usually established brands)

If you're wondering what Domain Authority is good for your site, aim to outperform your direct competitors rather than chasing a specific number.

How to Check Domain Authority

To check your Domain Authority, you can use several tools provided by Moz and other SEO platforms. Here are some common options:

• Moz Link Explorer
• Moz Domain Analysis Tool
• Free Chrome extensions like MozBar
• Third-party tools like Ahrefs, SEMrush, or Ubersuggest (they have their own metrics but similar in concept)

Where to Check Domain Authority

The most accurate source to check Domain Authority is directly through Moz.com. Their tools offer real-time analysis and backlink data that help you understand your site’s standing and opportunities for improvement.

Why Does Domain Authority Decrease?

Several factors can cause a drop in your Domain Authority score:

• Loss of backlinks or linking root domains
• Low-quality or spammy backlinks being removed or disavowed
• Changes in Moz’s algorithm or updates to their index
• Competitors improving their own link profiles
• Website issues like downtime, poor content, or lack of optimization

A temporary decrease isn't necessarily alarming, but consistent drops should prompt a thorough SEO audit.

Conclusion

Domain Authority is a powerful metric for understanding your website's ranking potential. While it’s not used by Google, it remains an essential tool for competitive analysis and strategic planning. To build and maintain a strong Domain Authority, focus on high-quality content, earning valuable backlinks, and staying consistent with SEO best practices. Monitoring your DA regularly can help you adapt to changes and improve your site’s visibility in search engines.