Why internal links matter
Internal links are how search engines find your pages and how they judge which ones matter, because every link passes on a share of the attention the linking page has earned. A good page that nothing links to is easy to miss, while a page linked from your strongest articles gets crawled often and ranks more easily. They are also one of the few ranking levers fully in your control, since you can add one today without waiting on anyone else.
What it checks
The check starts at your home page and follows its links the way a crawler would, adding a sample of the pages listed in your sitemaps so that pages nothing links to still turn up. For every link it notes where it sits, because a link in the body of an article says far more about the page it points to than a link in a menu, header or footer does. From that map it works out how many links each page receives, how many clicks it sits from the home page, and which pages receive none at all.
It also flags the links that need fixing: links to pages that no longer load, links to addresses that redirect, internal links marked nofollow, and anchors such as “click here” or “read more” that tell nobody what the next page is about.
How the suggestions are made
For each page that needs links, the tool compares its wording (title, H1, headings and body copy) with every other page it read, to find the pages on related subjects. It then looks inside those pages for a sentence that already uses a phrase from the page’s title or H1, and that phrase becomes the suggested anchor. Because the words are already there, each suggestion is a link to add rather than a sentence to rewrite, and the report quotes the sentence so you can find it in seconds. A page that already links to another is never told to link to it again.
How the crawl works
Pages are fetched by EghosaBot, which obeys robots.txt and its Crawl-delay setting. A run reads up to 300 pages, which keeps it quick and light on your server, and it leaves addresses with a query string alone, since those are mostly filters and tracking that would fill the crawl with copies of the same page.
Your report and your data
The check is free. It asks for your email address before it runs, and you only join the mailing list if you tick the box. Each report has its own private link, which works for 90 days and is then deleted along with everything the check gathered. The privacy policy explains the rest.