What is internal linking?

Short answer

Internal linking is how the pages on your own site link to each other. It decides how Google finds your pages, which ones it treats as important, and what it thinks each one is about. It needs no new content, no backlinks and usually no developer, which makes it the cheapest ranking lever most sites have and the one they use least.

Every site has internal links: the menu, the footer, the “related posts” block. Most sites treat those as the whole job. The links that do the most work are the ones inside the copy, from one page to another where the text is already talking about the thing being linked to. Those are the ones nearly every site is missing.

What internal links do

They help Google find pages. Google discovers most pages by following links from pages it already knows, and its documentation is direct about the consequence: every page you care about should have a link from at least one other page on your site. A page that exists only in a sitemap has a weak claim to Google’s attention.

They pass importance around. The authority your site earns from backlinks mostly lands on the homepage and a few popular pages. Internal links are how it reaches everything else. The pages with the most internal links pointing at them are, in effect, the pages your site says matter most.

They tell Google what a page is about. The anchor text, the clickable words, describes the destination. Google’s guidance is that good anchor text is descriptive, reasonably concise, and relevant to the page it points to.

And they help people. A reader who lands on one page and finds a link to exactly the thing they need next stays on your site.

What I find on almost every site

Across eleven audits over fifteen years, one finding turned up in every single one: most published pages carry no contextual internal links at all, and the ones that do carry one or two where the copy could comfortably hold six. I wrote that up as eleven audits, one finding in every single one.

The other patterns repeat too.

Orphan pages. Pages nothing links to. On one marketplace, 8,317 of 9,220 indexed pages could not be reached by clicking.
Starved money pages. Service pages, categories and location pages with the fewest internal links on the site, while the blog links to itself.
Anchors that say nothing. “Read more”, “click here”, “this post”.
Pages competing with each other. Two pages split for the same query because your own anchors point at both.

How much linking is normal

More than most people expect. The HTTP Archive found the median page carries 41 internal links, and the median on the top 1,000 sites is 129. Most of those are navigation. The contextual ones in the body text are a small share, and that is where the gap usually is.

What good internal linking looks like

Links in the body of the text, where the sentence is already about the destination. Anchor text that names what the destination is about, ideally in the words people search for. More links pointing at the pages that earn money than at pages that do not. Every page reachable within a few clicks of the homepage. And when two pages could answer the same query, your internal anchors consistently pointing at the one that should win.

What it is not

It is not a related posts plugin. Those link by tag or similarity to whatever is nearby, not to what needs support, and they sit in a block that reads as boilerplate.

It is not stuffing the same keyword anchor into every page. Vary the wording the way a person would, and keep it natural.

And it is not a one-off job. Every new page needs links in and out, or the problem grows back.

Where to start

List the ten pages that should earn you money. For each, find three to five other pages on your site that already discuss the same subject, and add a link from a relevant sentence in each one, with anchor text that describes the target. That alone often moves rankings on those pages within a few weeks of recrawling.

Why it is the cheapest lever you own

Every other way to move rankings costs new money. Content costs writers. Backlinks cost outreach, or cash, and depend on someone else’s judgement. Technical fixes cost developer time you have to queue for. Internal links cost none of that. They work on pages that already exist, they are entirely inside your control, and nobody can take them away. On most sites there is more ranking sitting unused in the existing link graph than in the next six months of publishing, and it takes days rather than quarters to put it to work.

Then repeat it for every new page you publish, both directions: links into the new page from older ones, and links out of it to the pages it supports.

If your pages are already there and nothing is pointing at them, my internal linking service maps every link on the site, builds an anchor plan from your Search Console data, and tells you which link goes where, in which sentence.