Domain Authority — Definition & Meaning
What is Domain Authority?
Domain Authority (DA) is Moz's 0-100 score predicting how well a website will rank in search. Ahrefs uses Domain Rating (DR), Semrush uses Authority Score (AS) — all three estimate the strength of a site's backlink profile relative to the whole web. Higher = stronger authority = easier ranking.
Key points
- DA / DR / AS are NOT Google metrics — Google has never published a domain-level authority score. Third-party tools reverse-engineer estimates.
- Bands: 0-20 new · 20-40 growing · 40-60 solid · 60-80 strong · 80+ top-tier.
- Score grows from earning links from other high-authority sites — quantity matters less than referring-domain quality.
- Score is relative and logarithmic — going from DA 40 to 50 is roughly 5x harder than 30 to 40.
- Use as a directional comparison ("am I stronger than this competitor?") not as an absolute ranking predictor.
Example
A new SaaS blog at DA 18 will not rank for "seo software" (top 10 all DA 70+) but can absolutely rank for "seo software for shopify plus stores" where the top 10 average DA 35.
Frequently asked questions
How is Domain Authority calculated?
Moz combines ~40 signals — mostly link-based (linking root domains, MozRank, MozTrust) — into a machine-learning model that predicts SERP position. Ahrefs' DR and Semrush's AS use similar but distinct blends.
How do I increase my Domain Authority?
Earn backlinks from high-authority relevant sites. Guest posts, digital PR, unique data studies, and being cited in industry roundups are the main levers. Buying links violates guidelines and rarely moves the score.
Is Domain Authority a Google ranking factor?
No — Google has confirmed DA is not used. But because it correlates strongly with the underlying signals Google DOES use (backlinks, brand mentions, quality), it remains a useful proxy.