Authority metrics are everywhere, and Semrush Authority Score is one of the most visible. It compresses a lot of domain-level data into a single number. That makes it convenient for quick judgment calls in link building, partnerships, and audits. It’s also easy to misread if you don’t know what goes into it.
Let’s keep it simple and explain what it measures, how it’s calculated, how it compares to DA and DR, and what counts as “good.”
What Is Semrush Authority Score?
Semrush Authority Score is a composite metric (0-100) that estimates a domain’s overall authority based on three pillars: backlink strength, organic performance, and spam risk.
In short: who links to you, whether your site actually ranks and gets traffic, and whether the link profile looks manipulated. It is not a Google metric. It’s a third‑party model built from Semrush’s dataset.
How Is the AS Calculated?
Semrush describe three components, calculated from eight weighted factors which together feed the three facets: Link Power (1), Organic Traffic (1), and Natural Profile (6):
Link Power
The quantity and quality of the backlinks a site has.
- Referring domains: count, quality, and growth trends
- Authority of linking domains: more influence from higher-authority referrers
- Link profile diversity: mix of domains, types, and follow vs. nofollow
- Link velocity: natural, consistent growth tends to correlate with higher scores
- Category (niche) relevance: relevant links carry more weight than equally strong but off-topic links, which better reflects topical credibility.
Organic Traffic
How much organic traffic a site approximately gets every month.
- Estimated organic traffic: if a domain earns actual search traffic, it signals trust and relevance.
- Keyword rankings: ranking distribution and stability feed into perceived authority.
Spam Factors (Natural profile)
These are manipulation indicators:
- No organic rankings on SERPs
- An unnaturally high % of do-follow domains
- An imbalance between links and organic traffic
- Too many referring domains with the same IP address
- Too many referring domains with the same IP network
- The presence of another domain with an identical backlink profile
The model rewards credible link equity and real search traction, and it discounts profiles with clear manipulation patterns.
How Semrush AS differs from Moz DA and Ahrefs DR
All three are useful. All three are third‑party metrics. None are used by Google.
The differences come down to inputs and sensitivity:
- Moz DA (Domain Authority): Based primarily on a machine learning model of link data. It’s solid for link-based comparisons and tends to be more responsive to link profile changes, but it doesn’t include organic traffic as a core signal.
- Ahrefs DR (Domain Rating): Heavily link-focused, with strong coverage of referring domains and link equity flow. Great for measuring raw link strength. Less emphasis on organic performance or spam patterns beyond link graph analysis.
- Semrush AS (Authority Score): Semrush blend link authority and organic traffic with spam detection. That mixed approach means a domain with lots of links but no rankings (or messy patterns) won’t necessarily look “strong.”
Semrush AS Cannot Be Manipulated Easily
Nothing is bulletproof, but AS is harder to inflate because six of its eight factors flag manipulation.
If you blast cheap links at a site, DR might wobble, DA might tick up temporarily – but AS will often resist because the organic and spam layers push back. If the links aren’t helping rankings – or worse, they look toxic – AS won’t reward them much. That’s the quiet genius here: it rewards outcomes, not just inputs.
What’s a Good Authority Score?
There isn’t a universal “good” AS – context is everything. It’s relative to your niche and the competitors you’re up against. A “good” AS for a local florist is different from a fintech publisher.
If your industry peers sit around 15 and you’re at 20, you’re in a strong position – even if 20 looks modest alone.
Higher is generally better, but on an absolute scale AS doesn’t tell you much; it’s mostly useful in comparison. But in general, your score is “good” when it’s higher than the sites you’re competing with.
Context matters – an AS of 10 can still struggle to rank if most rival domains are sitting at 40+. And keep in mind that a steady climb from 17 to 28 in six months can be more meaningful than sitting flat at 45.
A quick note for link builders: don’t ignore page‑level strength. A site at AS 35 with a page that ranks and gets real traffic can be an excellent placement. Relevance plus real audience beats a high score from a site your buyers never read.
Where Semrush Authority Score Fits in Your Workflow
- Prospecting: Sort by AS to reduce noise, then check topical relevance, traffic, and page-level metrics before pitching. The niche weighting now makes this cleaner.
- Risk checks: If AS is dragged down by Natural Profile indicators (e.g., identical backlink profile or IP clustering), proceed carefully.
- Monitoring: Track AS trends alongside organic traffic. Sudden drops can hint at link loss, PBN cleanup, or ranking declines.
- Reporting: AS is useful for directional trends and comparison against competitors, but combine it with real business metrics (traffic, conversions, revenue) for decisions.
Note for MeUp users: You can see an up‑to‑date Semrush Authority Score for each site on the platform for free.
Final Thoughts
So, should you rely on Semrush Authority Score? Well, the thing is, numbers are comforting, but they’re still numbers.
AS is clear about what it measures: link strength, organic traction, and spam risk. It’s stricter on manipulation signals than link-only metrics and now weighs topical relevance more heavily. Use it to prioritize and to spot red flags.
Pair AS with your marketer’s gut, your SERP checks, and a quick scroll through the site. If it reads like a place your audience would trust, you’re on the right track – even if the number isn’t flashy.