A hidden link is a link that exists in the code of a page but that a visitor cannot see or click. It is one of the oldest tricks in link spam. Someone who wants a link to a casino, a pharmacy or a dubious shop to be read by search engines, without readers or the site owner noticing it, tucks the link into an invisible element. The page looks the same as before, and the owner has no reason to look at the source.
Why it matters
A hidden link that is followed can pass ranking credit from your page to a site you have never heard of. Google’s link spam policies describe hidden links as a way of manipulating rankings, and a page that carries them can lose trust. Hidden links are also a very common sign that a site has been compromised, because the person who added them does not want them found. See after a WordPress hack for what a clean-up involves.
What it looks like
<div style="display:none">
<a href="https://example.net">anchor text</a>
</div>The same effect can be had by moving the link far off-screen, shrinking text to nothing, making it fully transparent or giving the container no width or height.
How Link Signals treats it
Link Signals marks a link as hidden when it, or one of its 7 nearest parent elements, uses one of 7 inline-style tricks, such as display:none, visibility:hidden, opacity:0 or left:-9999px, or has the hidden or aria-hidden attribute. If the same destination is linked more than once on a page, it is reported as hidden when any one of those links is.
A hidden link is not automatically a failure. Link Signals still looks at where it leads. A hidden link to a blocklisted domain is Not safe. A hidden link to a page that has nothing to do with the page carrying it is Needs review. Hidden links count as an out-of-context finding, which is the third priority in a report.
Common misunderstandings
- Not every hidden element is spam. Collapsed menus, tabs and accordions often use the
hiddenattribute for a good reason, so a hidden link to a trusted site is looked at before it is judged. - Only inline styles and attributes are read. A link hidden by a rule in a separate stylesheet cannot be seen by the scanner.
- A hidden link is not the same as cloaking, where the link is not in the page at all for an ordinary visitor.
The full list of techniques, and what the scanner cannot see, is on hidden links.
Questions
Can a hidden link be there on purpose?
Occasionally, for example a skip link or a menu that opens on a click. Hidden links to outside sites that nobody on your team can account for are the ones to investigate.
Should I just add nofollow?
Marking a hidden link nofollow stops it passing credit, but it does not explain how it got there. Find out first, then remove it. See which rel should a link have.
How this counts in your LinkSignal
Hidden links are counted in the hidden, cloaked and script-injected links row of your site’s external LinkSignal, once each. See how the score is worked out for the points and the LinkSignal overview for the other rows. LinkSignal is Link Signals’ own metric, worked out only from what this tool finds, and it is not connected to any search engine or third-party score.
Run a scan and find where these show up on your own site.
