Most internal linking guides tell you to "add more links." That advice is not wrong, but it is incomplete. Adding links without measuring the right metrics means you cannot know whether you are actually moving the needle, or just adding noise to your site's link graph.
This article covers the metrics that genuinely predict whether internal linking is working: what to track, which tools surface them, what benchmarks to aim for, and how to build a repeatable reporting process. No vanity metrics, no generic checklists.
Definition
Internal linking metrics are quantitative signals that describe the structure, health, and effectiveness of the hyperlinks connecting pages within a single domain. They include structural measures (crawl depth, orphan rate, inlink count) and behavioural measures (pages per session, bounce rate, time on page) that together reveal how internal links are performing for both search engines and users.
Link equity is not visible. You cannot see it move across a site, and Google does not provide a direct report showing how PageRank distributes internally. What you can measure are the proxies: how many links point to each page, how deep that page sits in the architecture, how users behave after following internal links, and whether pages that received additional links subsequently gained organic traffic.
These proxies are meaningful. A blog that improved its internal linking structure saw organic traffic increase by 43% over six months.[1] That result came from a combination of fixing orphan pages, improving crawl depth, and distributing equity more deliberately to money pages.
Myth: More internal links always mean better rankings. Research on 23 million links found that pages peak at around 45-50 inbound internal links. Beyond that, traffic tends to decline as equity becomes diluted across too many links.[2]
Myth: Sitewide navigation links count the same as contextual body links. They do not. Google's "Reasonable Surfer" model suggests that links in prominent, relevant positions pass more equity. Contextual links from topically related content are significantly more powerful than footer or sidebar links on unrelated pages.
Myth: You only need to audit internal links when something breaks. Proactive, regular auditing is what drives long-term organic growth. Sites that run regular audits see organic traffic gains of 61% on average.[3]
Crawl depth measures how many clicks separate a page from the homepage. Pages at depth 1-3 receive nine times more organic traffic than pages at depth 4 or below.[2] This is not a coincidence. Pages that are harder for users to reach are also harder for Googlebot to discover and re-crawl. They receive fewer internal links by definition, which also means less equity.
Your report should show the distribution of crawl depth across all indexed pages. Aim for all high-priority content (money pages, product pages, core service pages) to sit at depth 3 or fewer. Flag anything important sitting at depth 4+ as a structural fix.
9x
more organic traffic for pages within 3 clicks of the homepage
Source: inblog.ai
An orphan page is one with zero internal links pointing to it. Googlebot cannot discover orphan pages through crawling. Even if they are submitted via XML sitemap, they receive no link equity and therefore have almost no chance of ranking for competitive terms.
The average site has orphan pages accounting for roughly 22% of its content. Orphan pages receive only 5% of organic visits, compared to 95% for linked pages.[1] Fixing orphan pages by adding relevant internal links to them has produced traffic increases of up to 106% in documented cases.[4]
22%
average proportion of site content that is orphaned (no internal inlinks)
Source: Linkify case study analysis
"Orphan pages and dead ends should always be linked somewhere relevant. They represent wasted content investment that better internal links can activate."
Svitlana Shchehel, Content Team Lead, SE Ranking
The number of unique internal pages linking to a URL is its inlink count. This is a direct proxy for the amount of link equity a page accumulates from within the site. Your report should show inlink count for every important page, and flag pages with low inlink counts that are targeting valuable keywords.
Research from Ahrefs confirms that pages with 10 internal links perform approximately 30% better in organic search than pages with fewer links, holding other factors constant.[5] For money pages, a target of 10-20 inlinks from relevant contextual content is a sensible starting point.
How many links a page sends out affects how much equity it retains. Pages that link to dozens of destinations distribute their equity thinly. This matters most for high-authority pages (like your homepage or major hub pages): every additional outlink they send slightly reduces the equity flowing to each destination. Audit out-degree alongside in-degree to identify pages that are overly generous with their links.
Anchor text tells search engines what the linked page is about. Research from Semrush across 10 million pages found that 25% of internal links use generic anchors like "click here" or "read more".[6] Generic anchors pass no topical signal. Your report should show the anchor text breakdown for each priority page, and flag pages that lack any exact-match or descriptive anchors.
"Mixing anchor text sends diverse signals. If all your internal links use the same anchor, you are leaving topical variety on the table."
Kennedy Ingbre, SEO Manager, Varner
Pages per session measures how many pages a visitor views in a single session. Good internal linking drives this metric up by making relevant next steps obvious and easy to follow. A site with thoughtful contextual links to related content will naturally see higher pages per session than one with sparse or generic links.
Compare pages per session between pages with strong internal link structures and those with few inlinks. The difference is usually significant, and it directly informs where to prioritise link-building efforts.
When visitors arrive on a page and immediately leave, it often signals a mismatch between what they expected and what they found. But it can also indicate a lack of obvious next steps. Internal links to related, relevant content give visitors reasons to stay and explore. Pages with well-placed contextual links typically see lower bounce rates than equivalent pages without them.
Track these metrics per-page rather than site-wide. Site-wide averages mask the variation that makes this data useful. A page with a bounce rate of 80% might simply be serving a "find and leave" need, or it might be failing to retain visitors who would benefit from deeper content.
GSC's Links report (under the "Links" section) shows top internally linked pages and, for each page, which internal pages link to it. The limitations: data is sampled and capped at 1,000 rows per table. It does not show anchor text, link position, or whether links are navigational or contextual. It is best for a high-level view of which pages receive the most internal links, and for spotting pages with very few inlinks.
Ahrefs Site Audit surfaces orphan pages (flagged as "No incoming internal links"), inlink counts, crawl depth per URL, and broken internal links. The internal links report exports as CSV with source URL, destination URL, anchor text, and follow/nofollow status. This is the most actionable dataset for structural analysis. The orphan page report is particularly reliable since it is based on a full crawl rather than a sample.
Semrush flags internal linking issues in its Site Audit under "Internal Linking" and "Crawlability". It reports on broken internal links, pages with only one inlink, pages with no internal links, and redirect chains. The issues are scored by severity, which helps with prioritisation.
Linki processes your site's full link graph and surfaces all key structural metrics in a single report: orphan pages, crawl depth distribution, inlink counts, anchor text variety, and redirect chains. Rather than requiring manual export-and-cross-reference between multiple tools, Linki presents a prioritised action list based on the SEO value of each issue. See how it compares in our internal link checker tools comparison.
| Metric | Target | Warning Threshold | Source |
|---|---|---|---|
| Orphan page rate | <5% of pages | >15% | Linkify case study |
| Crawl depth (priority pages) | ≤3 clicks | 4+ clicks | My Rankings Metrics |
| Inlinks per money page | 10–50 | <5 | Zyppy 23M links study |
| Generic anchor text rate | <10% | >25% | Semrush 10M pages |
| Broken internal links | 0 | Any | Industry standard |
| Redirect chains | 0 | Any multi-hop chain | Industry standard |
106%
traffic increase recorded after fixing orphan pages in documented cases
Source: Google Penalty analysis
Run through this checklist monthly for active sites, and quarterly for stable ones:
For the full workflow on running site-wide audits on large sites, see our guide on auditing internal links at scale. For fixing orphan pages specifically, our orphan pages fix guide covers the prioritisation and implementation process in detail.
Research on 23 million internal links found that pages with 45-50 inbound internal links see the highest organic traffic. Below 10 inlinks, pages are significantly underperforming their potential. Above 50, traffic begins to decline as link equity becomes diluted. For practical purposes, aim for 10-20 inlinks for most pages, and 30-50 for your most important commercial or pillar content.
The most reliable approach combines structural metrics (orphan rate, crawl depth, inlink count per priority page, anchor text distribution) with behavioural metrics (pages per session, bounce rate) and outcome metrics (organic clicks and impressions in GSC for pages that received new inlinks). Track changes over 4-12 weeks after each internal linking intervention to isolate impact.
Orphan pages are pages with no internal links pointing to them from elsewhere on the site. Googlebot cannot discover them through crawling and they receive no link equity, which means they almost never rank for competitive terms. On average, 22% of site content is orphaned. Fixing orphan pages by adding relevant contextual links has produced traffic increases of up to 106% in documented cases.
Pages per session is the most direct behavioural indicator: if internal links are working, visitors follow them and view more content. Time on page increases when relevant related content is surfaced. Bounce rate decreases for pages with strong contextual links to related content. Track these per-page, not as site averages, to identify where internal linking is working and where it is not.
For actively publishing sites, a monthly structural review (orphans, broken links, new pages with low inlinks) plus a quarterly full audit covering depth, anchor text, and equity distribution is a practical cadence. Automated tools like Linki can surface new issues as they arise, which is more efficient than relying solely on scheduled manual checks.
Sources