Domain Authority
Domain Authority (DA) is a proprietary 0–100 score developed by Moz that predicts how likely a domain is to rank in search engine results pages. A higher DA indicates a stronger domain, in Moz’s model.
Example
A brand-new website with no inbound links might have a DA of 1–5. A major news publication like the BBC has a DA of 95+. Most SMB websites that have been running for 2–3 years and have made some effort at link building fall in the 20–45 range.
How it’s Calculated
DA is computed using a machine-learning model that incorporates several inputs:
- Referring domains — the number of unique domains linking to yours
- Link quality — the DA of the domains linking to you (links from high-DA sites carry more weight)
- Spam signals — Moz’s spam score filters out links from manipulative or low-quality sites
- Historical data — DA changes slowly; a single viral link does not dramatically shift your score overnight
Moz recalculates DA for all domains it tracks regularly. Changes in your DA often reflect changes in competitors’ scores rather than changes in your own link profile.
Why It Matters
DA is the most-cited third-party domain metric in B2B sales conversations, outreach emails, and agency pitches. When a client asks “what’s your DA?” they are asking specifically about this Moz metric.
For your own strategy, DA is a useful signal for:
- Benchmarking against competitors — if your DA is 25 and your top competitor is 55, you know the gap you’re trying to close
- Qualifying outreach targets — before spending time on a link-building prospect, a DA check tells you whether a link from that domain would meaningfully improve your profile
- Tracking progress over time — a rising DA across 6–12 months is a lagging indicator that your link building is working
What It Is Not
DA is not a Google ranking factor. Google uses its own PageRank algorithm, which is not publicly accessible. Moz’s DA correlates with ranking performance — sites with higher DA tend to rank better — but the correlation is not causation. Google has confirmed multiple times that third-party metrics including DA, DR, and Authority Score do not directly affect search rankings.
Tools That Show This Metric
- Moz Pro at $99/mo (Standard) — the original and still the most widely cited; Moz Pro includes full DA tracking for all domains
- MozBar (free Chrome extension) — shows DA on any web page as you browse, at zero cost
For domain rating (DR) — Ahrefs’ equivalent metric — see the Ahrefs review. For Authority Score — Semrush’s composite metric — see the Semrush review.