Domain authority

Definition

Domain Authority (DA) is a search engine ranking score developed by Moz to estimate how likely a website is to rank on search engine results pages (SERPs). The score ranges from 1 to 100, with higher numbers indicating a stronger potential for ranking. It is based on factors such as backlink quality, linking root domains, and overall site authority.

Although not a Google ranking factor, Domain Authority is widely used as a comparative metric to gauge a website’s SEO strength relative to competitors. For instance, if two competing sites target the same keyword, the one with a higher DA often has a greater chance of achieving higher visibility.

Advanced

Unlike Google’s undisclosed ranking signals, Domain Authority is a predictive model built by Moz. It uses machine learning to correlate data such as link quantity, link quality, MozRank, and MozTrust with known search results. The score is logarithmic, meaning it is easier to move from 20 to 30 than from 70 to 80.

DA is best interpreted as a relative measure rather than an absolute score. Marketers often track Domain Authority alongside Page Authority, competitor benchmarking, and link-building efforts. While Moz pioneered DA, similar metrics exist such as Ahrefs’ Domain Rating (DR) and SEMrush’s Authority Score, each relying on proprietary calculations but serving the same purpose—estimating ranking potential.

Why it matters

• Helps businesses benchmark SEO strength against competitors.
• Provides a directional measure of link-building effectiveness.
• Guides outreach and partnership decisions by evaluating site quality.
• Acts as a proxy indicator of a website’s ability to gain organic visibility.

Use cases

• Assessing the value of potential backlink opportunities.
• Comparing competitive websites for keyword targeting.
• Tracking improvements after a link-building campaign.
• Evaluating domains for guest posting or partnerships.

Metrics

• Domain Authority score (1–100).
• Number of linking root domains.
• Quality and relevance of inbound links.
• Comparative shifts in DA versus competitors.

Issues

• Misinterpretation of DA as an official Google ranking factor.
• Overemphasis on score rather than actual organic traffic or conversions.
• Manipulation risk through low-quality link schemes.
• Variability between Moz, Ahrefs, and SEMrush authority metrics.

Example

A digital marketing agency is comparing two potential partners for link outreach. One website has a DA of 25, while the other has a DA of 70. By choosing the higher authority site, the agency secures backlinks that significantly improve its client’s search visibility and ranking performance.