A link farm is a group of websites that all hyperlink to the other sites in the group to raise their search rankings [1]. For example, 50 thin sites about unrelated topics (insurance, dog food, crypto, wedding venues) might each carry a "partners" page linking to all 49 others, so every site appears to have dozens of backlinks.

In graph terms, a link farm is a clique: every member links to every other member [1]. The links exist to exploit link-based ranking, not because one site recommends another. That makes link farms a classic form of spamdexing, the broad practice of manipulating search engine indexes [2].

The term is also used loosely for any site that exists mainly to hand out links, such as a page of hundreds of unrelated outbound links sold to anyone who pays. The strict meaning is the interlinked network.

A link farm works by manufacturing link popularity. Search engines that count links as votes see each member of the farm receiving many inbound links and may treat it as more important than it is [1][2].

Early link farms ran on reciprocal linking: to receive links from the farm, a site had to link back [1]. That requirement was also the weakness. Members joined, collected inbound links and then hid or removed their own outbound links, forcing farm operators to police their members [1]. When Google introduced PageRank, which weights links by the importance of the linking page, link farm operators adapted, because a link's value now depended on where it came from rather than on raw counts [1].

Yes. Link farms break Google's spam policies, which define link spam as "creating links to or from a site primarily for the purpose of manipulating search rankings" [3]. Several of Google's listed examples describe how link farms operate [3]:

  • Excessive link exchanges ("Link to me and I'll link to you") or partner pages exclusively for the sake of cross-linking.
  • Using automated programs or services to create links to a site.
  • Creating low-value content primarily to manipulate linking and ranking signals.
  • Buying or selling links for ranking purposes.

Google's policy does not need the words "link farm" to apply. Any network whose links exist for rankings falls under it.

Sites in a link farm risk having those links ignored, receiving a manual action, or in severe cases being removed from search results. The outcomes, from mildest to worst:

  • Links ignored. Google's automated systems, including SpamBrain, remove the effect of spammy links, and "any ranking benefit the links may have previously generated for your site is lost" [5][6].
  • Manual action. A Google reviewer can issue an unnatural links action for links pointing to a site, or for links leaving it [4]. A link farm member can earn both.
  • Removal from results. Sites that violate Google's spam policies "may rank lower in results or not appear in results at all" [3]. Early search engines removed some link farm domains from their indexes entirely [1].

A link farm is a network of sites linking to each other, while a private blog network (PBN) is a set of sites one owner controls to send links to a separate main site. A PBN is usually built from expired domains that already have backlinks, and it points outward to one or a few "money" sites [2]. A link farm points mainly inward, with members boosting each other.

Link farmPrivate blog network
Link directionMembers link to each otherNetwork links out to the owner's main site
OwnershipOften many members joining a schemeUsually one owner, hidden [2]
Typical sitesThin, unrelated, open to anyoneExpired domains with existing backlinks [2]
Google policyLink spam [3]Link spam [3]

Search Insider does not support or suggest the use of private blog networks. Both tactics break the same policy, and Google targeted PBN users with penalties starting in 2014 [2].

A link exchange is two sites agreeing to link to each other, while a link farm is that trade scaled up to a whole network. Google's spam policies do not ban every reciprocal link. They ban excessive link exchanges and partner pages built only for cross-linking [3]. Two related businesses that recommend each other once are not a link farm. Fifty unrelated sites linking in a ring are.

To spot a link farm, look at the linking site's outbound links and ask whether a reader would ever click them. These are practical warning signs, not a Google checklist:

  • Unrelated outbound links. A single page links to casinos, plumbers and skincare brands with no common thread.
  • Partner or resources pages that are just link lists. Hundreds of links, no descriptions, no reason to exist for a reader. Google names "partner pages exclusively for the sake of cross-linking" as link spam [3].
  • Thin, templated sites. The same design, the same short articles and the same footer links across many domains.
  • Reciprocal demands. A site will only link to you if you link back.
  • No real audience. No brand searches, no social presence, and content written for keywords rather than people.

If several of these appear together, treat a link from that site as worthless at best and a risk at worst. In a backlink audit, links from link farms are the clearest case for removal, and for a disavow file if a manual action is involved.

Link farms started in 1999, and search engines responded by filtering link farm pages and later by building systems that discount manipulative links automatically [1][6]. The dated history:

1999: link farms exploit Inktomi

Search engine optimizers first developed link farms in 1999 to take advantage of the Inktomi search engine's dependence on link popularity [1]. Inktomi regularly purged pages with few inbound links, so a farm of links kept obscure sites in its index [1].

After PageRank: filtering and domain removals

As Google's PageRank made link value depend on the linking page's importance, link farms adapted [1]. Search engines countered by identifying the attributes of link farm pages and filtering them from indexing and results, and in some cases removed entire domains from their indexes [1].

2012: Penguin

Google announced Penguin on April 24, 2012, to demote sites that manipulated the number of links pointing to them [7]. Google describes Penguin as "a system designed to combat link spam" [6].

2016 onward: links discounted, not counted

Penguin became part of Google's core ranking systems in 2016 [6], and from then on it discounted bad links rather than demoting whole sites [7]. Google's current SpamBrain system continues that approach: link spam is neutralized and its benefit is lost [5].

No. A link farm offers links that Google's systems are built to ignore, with the added risk of a manual action [4][5]. Money and time spent on link farm links buy nothing that lasts. Links from relevant, real sites with their own audiences are the only kind worth building toward.