Link Building Metrics Explained: What You Need to Know

What Are Link Building Metrics?

Link building metrics are scores and measurements used to evaluate the quality, authority, and overall impact of backlinks pointing to a website. They are calculated by third-party SEO tools like Moz, Ahrefs, Majestic, and Semrush, each using their own algorithms and crawl data.

It is important to understand from the outset: none of these metrics are what Google uses to rank your site. Google stopped sharing its PageRank score publicly back in 2016. The tools you use today are approximations, built to fill that gap. They are valuable approximations, but you should never treat any of them as a ground truth.

What they are good for is filtering, prioritizing, and tracking trends over time. A domain authority ranking benchmarks guide can help you understand what scores mean in the context of your specific niche. And for the data behind why all of this matters, see our link building statistics roundup.

Authority Metrics: What Each One Measures

These are the metrics you will encounter most often when prospecting, vetting link placements, or reporting results to a client. Each tool has its own version of “domain strength,” calculated differently, which is why the same site can show DA 45, DR 30, and TF 18 at the same time. None of them are wrong. They are just measuring different things.

Domain Authority (DA) by Moz

Domain Authority is Moz’s score that predicts how likely a website is to rank on search engine results pages. It runs from 1 to 100 on a logarithmic scale, which means going from DA 20 to DA 30 is much easier than going from DA 70 to DA 80. DA accounts for linking root domains, total links, and Moz’s internal spam score, among other factors. It is one of the most widely recognized metrics in the industry, which also makes it one of the most over-relied-upon. A DA score says nothing about relevance and nothing about the actual quality of the site’s traffic. A DA 60 site that only covers tangentially related topics will pass far less value than a DA 25 site that is deeply embedded in your niche.

Domain Rating (DR) by Ahrefs

Domain Rating is Ahrefs’ equivalent of DA, but it is calculated differently and tends to be more aggressively link-based. DR is primarily determined by the number and quality of external backlinks pointing to the domain, weighted by the DR of those linking sites. Because it leans so heavily on backlink quantity, DR is more vulnerable to inflation via low-quality links than DA. A site with thousands of spammy directory links might show a deceptively high DR. That said, DR is still a useful directional indicator when you are doing competitive analysis at scale. For a deeper look at DA and DR together, our DA PA checker tools roundup covers the best free and paid options.

Page Authority (PA) by Moz

While DA measures an entire domain’s ranking potential, Page Authority zooms in on a single page. PA is scored the same way, 1 to 100, and factors in the links pointing specifically to that page rather than the domain as a whole. This matters for niche edits and link insertions: a page with PA 35 on a DA 20 site might actually be a stronger placement than a DA 40 site where the specific article you are getting a link from has PA 12 and zero inbound links of its own.

URL Rating (UR) by Ahrefs

URL Rating is Ahrefs’ page-level equivalent of DR. It reflects the strength of a specific URL’s backlink profile on a 0–100 scale, factoring in both external and internal links pointing to that page. UR prioritizes dofollow links. Nofollow links have minimal impact on this score. For link insertion campaigns, checking UR alongside the page’s organic traffic is a much better signal of link quality than looking at site-level DR alone.

Trust Flow (TF) and Citation Flow (CF) by Majestic

Majestic’s metrics take a different approach. Citation Flow measures the sheer volume of links pointing to a site, while Trust Flow measures how trustworthy those links are, based on how close they are to a manually curated set of seed sites that Majestic considers highly authoritative.

The real value here comes from looking at both together. A site with high CF and low TF has lots of links but they are low quality. A site with high TF and moderate CF has fewer but more trusted links. The Trust Ratio (TF divided by CF) gives you a quick quality signal. Scores close to 1.0 are healthy. Scores below 0.3 are a red flag. Examples: HubSpot sits at around 0.95, Forbes at around 1.06. A low-quality link farm might be 0.2 or lower.

Majestic also has Topical Trust Flow, which breaks down the trust score by category. This is useful for validating topical relevance when you are vetting a potential placement.

Authority Score (AS) by Semrush

Semrush’s Authority Score combines backlink data, organic search traffic, and spam factors into a single 0–100 score. Because it incorporates organic traffic data alongside link data, it is arguably a more complete picture of site health than pure link-based metrics like DR. The downside is that it can shift significantly with Semrush’s index updates in ways that feel disconnected from actual changes to a site’s link profile.

The Quality Signals That Actually Predict Ranking Impact

Authority metrics are useful filters. But the signals below are what separate a link building campaign that moves rankings from one that just looks good on paper.

Relevance

Relevance is the single most important factor in assessing link quality, and the one that third-party metrics measure worst. There are three layers to it: the relevance of the linking domain to your niche, the relevance of the specific page where the link is placed, and the relevance of the surrounding anchor text and context.

A single link from a topically aligned publication in your industry will outperform a dozen high-DA links from unrelated sites. Google’s own patents confirm that link relevance is a core part of how it weights link equity. No tool gives you a definitive relevance score. You have to assess it manually during prospecting.

Referring Domains

Referring domains measures the number of unique websites linking to your site. This is a stronger ranking signal than total backlink count. Ten links from ten different domains is almost always better than fifty links from two sites. Each new referring domain adds a new “vote” from a new source. After the first one or two links from any given domain, additional links from that same site offer diminishing returns in terms of link equity. When comparing your profile to competitors, always compare unique dofollow referring domains, not raw backlink counts.

Anchor Text Distribution

Anchor text is the clickable text used in a hyperlink. Google reads it as a signal of what the linked page is about. Your anchor text distribution should be a natural mix of branded anchors (your company or site name), naked URLs, partial-match keywords, generic phrases like “read more,” and some exact-match keywords for your target terms.

Over-optimizing with too many exact-match anchors is a classic over-optimization signal that can trigger algorithmic devaluation or a manual review. A healthy backlink profile from a natural-looking site will typically show a large proportion of branded and generic anchors, with keyword anchors making up a smaller percentage. Analyze your anchor text mix regularly using Ahrefs or Semrush, and compare it against your top-ranking competitors to calibrate.

Organic Traffic of the Linking Site

This is one of the most underrated signals in link prospecting. A site can have DA 50 and DR 40 with almost no real organic traffic, because the metrics were built through link manipulation and the site’s content does not actually rank for anything. If a site is getting real traffic from search, it means the content is genuinely indexed, relevant, and valued by Google. That is the kind of site you want linking to you.

Use Ahrefs or Semrush to check organic traffic estimates when vetting prospects. Set a baseline that makes sense for your niche. Also check the traffic trends: a site with declining traffic month over month is a warning sign even if the current number looks acceptable. And dig into the traffic composition. If 80% of the site’s keywords are unrelated to your niche, or if the top pages are about completely different topics, that is a relevance problem that no DA score can compensate for. Learning how to check backlink quality properly means going beyond the headline metrics to look at traffic and relevance together.

Spam Score

Moz’s Spam Score estimates the likelihood that a site has characteristics associated with Google penalties. It runs from 0 to 100%, where higher means more likely to be penalized. A score above 30% should prompt a closer look. It is not a perfect metric. Some legitimate niche sites can score high due to template similarities, but it is a useful red flag filter. Combine it with Trust Flow and traffic data for a more complete picture of site health.

Link Velocity

Link velocity is the rate at which your site gains or loses backlinks over time. A sudden, unnatural spike in new links, particularly after you launch an aggressive outreach campaign, can look suspicious to Google’s systems. A slow, steady build is always preferable. Velocity also matters in competitive terms: if a competitor is building 15 links per month and you are building 5, they are widening the gap. Tracking your link velocity monthly and comparing it to your top 3 competitors gives you a sense of how much ground you need to make up and at what pace.

Dofollow vs Nofollow Ratio

Dofollow links are the ones that pass link equity and directly influence rankings. Nofollow links carry the rel=”nofollow” attribute, which tells Google not to follow the link or treat it as an endorsement. A common misconception is that nofollow links are worthless. They do not pass PageRank directly, but they drive referral traffic, build brand visibility, and contribute to a natural-looking backlink profile.

A profile made up entirely of dofollow links is actually a red flag. Real websites naturally pick up nofollow links from social media, news sites, forums, and press coverage. If your profile has zero nofollow links, it can appear manufactured. Compare your dofollow-to-nofollow ratio against your top competitors to understand what a healthy mix looks like in your niche. The right balance varies, but a broadly natural profile usually shows 60-80% dofollow links depending on industry.

How to Use Metrics for Competitive Analysis

The most important rule in using any link building metric is to compare yourself only against direct competitors in the same niche. A “good” DA 40 might be dominant in one niche and weak in another. Comparing your scores against a site in a completely different vertical is meaningless.

Here is a practical approach. Pull the top 3 to 5 results for your most important target keywords. For each competing domain, note their DA, DR, unique dofollow referring domains, estimated organic traffic, and top anchor text categories. This gives you a benchmark for where your own profile needs to be to compete on those terms.

Then identify the link gap. For a given target page, how many unique dofollow referring domains does the top-ranking competitor have, versus you? That gap, adjusted for link velocity, tells you roughly how many links you need to build, and at what pace, to close in on that position. For a practical guide on this, see our post on how many backlinks to rank.

Also check which sites are linking to your competitors but not to you. These are warm targets for outreach since they have already demonstrated willingness to link within your niche. Our guest posting service handles this kind of targeted placement at scale if you want to close gaps quickly without running your own prospecting operation.

Metrics Worth Tracking vs Metrics to Stop Obsessing Over

A Practical Metrics Process for Link Building in 2026

Here is how to use these metrics together rather than in isolation.

Frequently Asked Questions