Every page here is about something the scanner actually checks. Each shows how the check works, what a flagged link looks like in a report, and where the check stops.
A hidden link is an outbound link that is in a page’s HTML but invisible to the people reading it. It is a common sign of injected spam, so Link Signals checks every link it finds for it.
Out-of-context links and how they’re flaggedA link can be fine on one page and wrong on another. Link Signals judges each outbound link against the page that carries it, which is how it tells a casino-review site from a gardening blog linking to a casino.
Finding pharma links injected into a siteA link to an online pharmacy on a gardening blog is one of the clearest out-of-context findings there is. This page lists exactly what the pharma check looks for and how a finding is graded.
Finding gambling links on your siteGambling is the one category with both a public blocklist and a keyword check, so a finding can be confirmed or only needs review. Here is how each is decided.
Cloaked links: shown to Google, not to youA cloaked link is served to search-engine crawlers, or to visitors who arrive from a search, but not to someone opening the page directly. That is how injected spam stays hidden from the site owner.
Links hidden in scripts: how they’re foundSome injected links are not in the page’s HTML at all. A script writes them in when the page loads, often from an encoded string. Link Signals reads a page’s inline scripts and decodes the common encodings.
Expired domains: the link risk beyond 404sMost tools tell you a link is broken. The bigger risk is that the domain behind it has lapsed and someone has registered it on purpose, to put their own content where your link already points.
Links to domains anyone can registerA page that links to a domain nobody holds hasn’t just lost a destination. Whoever registers the domain next decides what that link points at.
Parked and for-sale domains in your linksA parked page is what a lapsed domain often shows before anyone builds on it. A link to one points at a site that is gone and a domain that is up for grabs.
Links to newly registered domainsA domain registered days ago, linked from an established page, is unusual. It is how a re-registered expired domain looks, and how a throwaway campaign domain looks.
Broken links (404) in a scan reportA broken link points to a page that returns 404 or 410, so the destination has gone. This page explains exactly what the report lists, where it ranks, and what to do.
Malware and phishing links in a scan reportThe Malware and phishing card lists outbound links that lead to destinations judged to be malware or phishing. It is a high-risk card, and one that is worth acting on the same day.
Adult content links in a scan reportThe Adult content card lists outbound links to adult sites. They are either intended on an adult-themed site, or an unwelcome surprise on any other site, so the first job is to decide which.
Illegal drug links in your scan reportThe Illegal drugs card lists outbound links whose destination looks like it sells or promotes illegal drugs. This page explains what puts a link on that list and what to do about each one.
Payday loan links in your scan reportThe Payday loans card lists outbound links to short-term, high-cost lending pages. A regulated lender you chose is one thing; an unrelated link nobody chose is another.
Violent content links in your scan reportThe Violence card lists outbound links to graphic violence. Unlike drugs, loans and hate, this category has a public blocklist, so a finding can be a confirmed list match.
Hate content links in your scan reportThe Hate card lists outbound links to pages that look like hate groups or hate material. Research and reporting about hate can match too, so each one needs a person to judge it.