What is backlink monitoring?
Backlink monitoring is the practice of re-checking the links you have earned to confirm they are still there, still dofollow, and still using the anchor text that was agreed. It is maintenance rather than discovery, and it is the half of backlink management that most teams skip.
Backlink monitoring vs. a backlink checker
A backlink checker answers "what links does this domain have?" using a crawled index. A backlink monitoring tool answers "did the link I earned in March survive?" — a much smaller question, and the one that determines whether a campaign actually worked. You need both, but only one of them is about your own work.
Why links disappear
Editors redesign pages. Sites migrate CMS and drop outbound links. Someone runs an SEO audit and nofollows everything external. A post gets consolidated into another and the link goes with it. None of these come with a notification, which is why a link you counted six months ago may not exist today.
What to do about backlink reclamation
A removed link from a site that already published you is the easiest link in your pipeline to get back — the relationship exists and the editorial decision was already made once. Reclamation usually converts far better than cold outreach, provided you find out in time to ask.