What Is a Website Authority Score — and Why Does Semrush Say 6 While Ahrefs Says 20?
If you've spent any time in SEO tools, you've run into some version of an authority score. Semrush has one. Ahrefs has one. Moz has Domain Authority. They all claim to measure roughly the same thing — how credible and powerful a domain is in the eyes of search engines — and they almost never agree with each other.
Right now, as of May 22, 2026, Ritner Digital's Semrush Authority Score is 6, flagged as "low authority." Pull up the same domain in Ahrefs and the Domain Rating comes back at 20. Same domain. Same day. Fourteen points apart.
That gap is confusing if you don't know what's underneath the numbers. It's also completely normal — and understanding why the gap exists tells you something important about what these scores actually measure and how much weight to give them.
What Authority Scores Are Trying to Measure
Before the tools, the concept.
Google has never published a single public metric for domain authority. PageRank — the original link-based signal Google's algorithm was built on — was publicly visible for years through a browser toolbar and then quietly retired as a public-facing metric in 2016. Google still uses link-based signals internally, but it doesn't hand you a number.
So the major SEO tools built their own. Each one attempts to model how authoritative a domain is based on the signals they can measure — primarily the quantity and quality of backlinks pointing to it. The idea is that a domain with many strong, credible sites linking to it is more likely to rank well than a domain with few links or links from low-quality sources.
The scores are proprietary models. They are not Google metrics. They do not directly determine your rankings. They are useful proxies — estimates — built on each tool's own crawl data and weighting methodology. And because each tool crawls the web differently, weights signals differently, and indexes different subsets of the internet's link graph, they produce different numbers for the same domain.
That's why Semrush says 6 and Ahrefs says 20. Neither is wrong. They're measuring the same underlying reality through different lenses.
How Semrush Calculates Authority Score
Semrush's Authority Score runs on a scale of 0 to 100. It's primarily driven by three categories of signals:
Link power. The quantity and quality of backlinks pointing to the domain. This includes the number of referring domains — unique sites linking to you — and the authority of those linking domains. A link from a high-authority publication carries more weight than a link from a low-authority blog.
Organic search traffic. Semrush incorporates estimated organic traffic into its Authority Score calculation, which is a meaningful difference from some competing tools. A domain that ranks for many keywords and drives consistent organic traffic gets a signal boost beyond just its link profile. This makes the Semrush score somewhat more reflective of actual search performance rather than just link accumulation.
Spam signals. Semrush also evaluates the quality of the inbound link profile. Domains with a high proportion of spammy or low-quality inbound links get penalized in the score even if raw link volume is high.
A score of 6 on Semrush's scale is genuinely low — it reflects a domain with a limited backlink profile, relatively few referring domains, and organic traffic that hasn't yet reached the threshold that meaningfully boosts the score. For a domain that's still in early development, a 6 is an accurate baseline, not an anomaly.
How Ahrefs Calculates Domain Rating
Ahrefs' Domain Rating — commonly called DR — runs on the same 0 to 100 scale but uses a different methodology and, critically, a different crawl database.
Ahrefs is widely considered to have one of the largest and most frequently updated link indexes in the industry. Its Domain Rating calculation is almost entirely link-based — it looks at the number of unique domains linking to you and the DR of those linking domains, using a logarithmic scale where moving from 70 to 80 is significantly harder than moving from 10 to 20.
The key difference from Semrush: Ahrefs DR does not incorporate organic traffic estimates. It is purely a link-based metric. This means two domains with identical link profiles would receive the same DR even if one drives ten times the organic traffic of the other.
It also means Ahrefs DR can sometimes read higher than Semrush Authority Score for newer or smaller domains — because Ahrefs is only counting links, and if those links are relatively clean and come from decent referring domains, the score can move faster than Semrush's more composite calculation.
A Domain Rating of 20 from Ahrefs reflects a domain with a modest but real link profile — enough referring domains of sufficient quality to register as a meaningful starting point. It's not high, but it's not negligible either. On Ahrefs' logarithmic scale, moving from 0 to 20 is actually more progress than the raw number suggests.
Why the Gap Between the Two Numbers Makes Sense
The 14-point difference between Semrush's 6 and Ahrefs' 20 comes down to a few specific factors:
Different crawl databases. Each tool has crawled different portions of the web and discovered different links. Ahrefs may have indexed backlinks that Semrush hasn't crawled yet, or vice versa. This is the most common source of divergence between tools.
Semrush factors in organic traffic, Ahrefs doesn't. Because Ritner Digital's organic traffic is still in early stages — as the Search Console data makes clear — Semrush's composite score gets pulled down by the traffic component in a way that Ahrefs' purely link-based DR doesn't. As organic traffic grows, the Semrush score will respond to that growth in addition to link growth.
Scale differences. The two tools calibrate their scales differently. A 6 on Semrush and a 20 on Ahrefs may reflect more similar underlying link profiles than the numbers suggest — they just sit at different positions on each tool's respective curve.
Log scale compression. Both tools use logarithmic scaling, which means the difference between 6 and 20 on either scale is smaller in real terms than it looks. Going from 20 to 40 on Ahrefs requires dramatically more link authority than going from 0 to 20.
What Either Number Actually Means for SEO
Here's the part that gets lost in the tool comparison: neither score directly determines your Google rankings.
Google does not use Semrush Authority Score or Ahrefs Domain Rating in its algorithm. These are third-party models. They correlate with ranking ability — domains with higher scores tend to rank more easily for competitive terms — but the correlation is not causation, and the scores are not inputs to Google's system.
What actually matters is the underlying reality the scores are attempting to model: the quantity of credible sites linking to your domain, the quality and relevance of those links, and the overall trust and authority signal your domain sends to Google. Improving those underlying signals will move both tool scores over time — but more importantly, it will improve your actual search performance.
For Ritner Digital at this stage, both scores are telling the same story: the link profile is real but limited. There are referring domains pointing to the site — Ahrefs can see enough of them to push the DR to 20 — but the total volume and authority of those links hasn't reached the threshold where either tool considers it a strong domain. That's an accurate reflection of a domain that's been building its organic presence through content rather than active link acquisition.
What Moves These Scores
Both scores respond to the same fundamental inputs, even if they weight them differently:
Earning links from high-authority referring domains. One link from a DR 70 publication does more for your Ahrefs score than fifty links from DR 5 blogs. Quality of referring domains matters more than raw link count at this stage. Digital PR, expert commentary in industry publications, and getting cited by authoritative sources in the marketing and SEO space are the highest-leverage link acquisition paths for a domain at this authority level.
Growing the referring domain count. Beyond quality, diversity matters. A healthy link profile has links from many different domains, not just a handful of strong ones. Expanding the number of unique sites linking to ritnerdigital.com — through content that earns citations, partnerships, directory listings in legitimate directories, and earned media — builds the breadth that both tools reward.
Organic traffic growth — specifically for Semrush. Because Semrush incorporates traffic estimates into its Authority Score, growing organic search traffic is a direct input to improving that specific number. This creates a useful alignment: the content program that grows your keyword portfolio and organic traffic also directly improves your Semrush Authority Score, independent of link acquisition.
Time and consistency. Both scores are lag indicators. Link building and content authority compound over months, not days. A domain at Authority Score 6 and DR 20 today, executing a consistent content and link acquisition program, should expect to see meaningful score movement over a 12 to 18 month horizon — not a 30-day one.
The Honest Bottom Line
Semrush says 6. Ahrefs says 20. Both are accurate given their respective methodologies. Neither number is your Google ranking signal. Both numbers are telling you the same underlying truth: the domain has a real but early-stage authority profile with meaningful room to grow.
The scores will move as the content compounds, as the organic traffic grows, and as more credible sites link to the domain. Watching both numbers over time — not as absolute verdicts but as directional trend indicators — is one of the more honest ways to track whether the foundational work is producing results.
The goal isn't a specific number on either tool. The goal is the underlying authority those numbers are attempting to measure. Build that, and the scores follow.
Want to understand where your domain's authority stands and what a realistic path to improving it looks like? Ritner Digital offers SEO audits and strategy built around what actually moves the needle.
Frequently Asked Questions
Is Semrush Authority Score or Ahrefs Domain Rating more accurate?
Neither is more accurate in an absolute sense — they're measuring the same underlying reality through different methodologies and different crawl databases. Ahrefs is widely regarded as having one of the largest and most current link indexes in the industry, which makes its DR a reliable read on your link profile specifically. Semrush's Authority Score incorporates organic traffic estimates in addition to link signals, which makes it a more composite measure of overall domain health. The most useful approach is to track both over time as directional indicators rather than treating either one as the definitive verdict on your domain's authority.
Does Google use these authority scores in its ranking algorithm?
No. Semrush Authority Score and Ahrefs Domain Rating are third-party proprietary metrics. Google does not use either of them. What Google uses are its own internal link-based signals — descendants of the original PageRank algorithm — along with hundreds of other ranking factors that no external tool has complete visibility into. The third-party scores correlate with ranking ability because they're modeling the same underlying signals Google cares about, but correlation is not the same as causation. Improving your actual link profile and organic authority improves your rankings. The tool scores follow as a byproduct, not the other way around.
Why did my Semrush Authority Score drop even though I didn't lose any links?
Several things can cause a score drop without a direct change to your link profile. Semrush periodically updates its algorithm for calculating Authority Score, which can shift scores across the board. If domains that were linking to you lost authority themselves, your score can decline even if the links are still technically active. Semrush also re-crawls the web continuously, and links it previously counted may be recrawled and reweighted. Additionally, if your organic traffic estimates decline in Semrush's data — due to ranking fluctuations — that traffic component can pull the composite score down. A score fluctuation of a few points in either direction without a clear cause is usually algorithmic noise rather than a meaningful signal.
What's a good Authority Score or Domain Rating to aim for?
It depends entirely on the competitive landscape of the keywords you're targeting. Authority scores are relative, not absolute. A DR of 30 might be more than enough to rank well in a low-competition niche and completely insufficient in a highly contested space where every competitor is above DR 70. Rather than targeting a specific number, benchmark against the domains currently ranking for your target keywords. If the top-ranking pages for your priority terms belong to domains with DR 40 to 60, that gives you a meaningful target range. Chasing a number in isolation without that competitive context produces vanity metrics rather than strategic clarity.
How long does it take to meaningfully improve an authority score?
For a domain starting in the single digits on Semrush or the teens on Ahrefs, meaningful movement typically requires six to twelve months of consistent effort — and that assumes active link acquisition alongside content development, not content alone. The logarithmic scale both tools use means early gains come faster than later ones: moving from 6 to 15 on Semrush is achievable faster than moving from 40 to 50. The inputs that move the score — earning links from credible referring domains, growing organic traffic, building content that attracts citations — all take time to compound. Monthly tracking is useful for spotting trends, but quarterly comparisons give a more honest read on whether the trajectory is moving in the right direction.
Can I improve my Semrush Authority Score without building backlinks?
Partially. Because Semrush incorporates organic traffic estimates into its Authority Score calculation, growing your organic search traffic through content — without any active link building — will put upward pressure on your score over time. This is a meaningful difference from Ahrefs DR, which is purely link-based and won't move without link acquisition. In practice, the fastest path to improving your Semrush Authority Score combines both: a content program that grows organic traffic and earns natural citations, paired with intentional outreach for higher-authority backlinks. Relying on content alone will move the score, but more slowly and with a lower ceiling than an integrated approach.
What's the difference between Domain Authority, Domain Rating, and Authority Score?
These are three different proprietary metrics from three different companies. Domain Authority is Moz's metric, running on a 0 to 100 scale and based primarily on the link profile of a domain. Domain Rating is Ahrefs' metric, also 0 to 100, also primarily link-based but calculated using Ahrefs' own crawl database and weighting methodology. Authority Score is Semrush's metric, 0 to 100, and the most composite of the three — incorporating link signals, organic traffic estimates, and spam detection. All three are attempting to model the same underlying concept of domain authority. All three will give you different numbers for the same domain. None of them is a Google metric, and none of them should be treated as a single source of truth.
Should I be worried that Ritner Digital's Authority Score is flagged as "low" in Semrush?
Worried, no. Aware and working on it, yes. A score of 6 on Semrush is an accurate reflection of a domain in early development — real authority is being built, but the link profile and organic traffic haven't yet reached the thresholds that move the composite score meaningfully. The Ahrefs DR of 20 is a slightly more generous read of the same reality and suggests the link foundation is more developed than the Semrush score alone implies. The practical implication is that highly competitive keywords will be harder to rank for at this authority level, which makes topical focus and content depth more important — concentrating ranking effort in specific areas rather than spreading thin across many competitive terms simultaneously.
Do authority scores matter for local SEO specifically?
Less than they do for broad organic search, but they're not irrelevant. Local SEO rankings — particularly in the Google Maps 3-pack — are driven primarily by Google Business Profile signals, review volume and quality, proximity, and local citation consistency. A low domain authority score doesn't prevent a local business from ranking well in local pack results. Where domain authority becomes more relevant in a local context is for the organic website results that appear below the local pack — ranking a service page for "digital marketing agency Philadelphia" in organic results requires more domain authority than ranking in the local map pack for the same query. For businesses competing primarily in local search, GBP and review optimization will move the needle faster than link building focused on authority scores.
Want to understand your domain's authority profile and what a realistic improvement roadmap looks like? Ritner Digital builds SEO strategy grounded in where you actually are, not where you wish you were.