Facebook’s friend suggestion algorithm is complex and considers many factors when recommending potential friends. However, you may occasionally see suggestions that appear to have no mutual friends or other obvious connections. Here are some of the main reasons Facebook may suggest friends with no mutual friends:
1. Location and proximity
If you and another Facebook user frequently check in or access Facebook from the same location, you may show up in each other’s suggestions. This is because Facebook’s algorithm assumes that people who live in the same area or visit the same places may know each other or share common interests.
For example, if you often check-in at a certain coffee shop or park in your neighborhood, Facebook may suggest local residents who also visit those places regularly. Even though you don’t have mutual friends, the location data indicates you likely live nearby and may run in similar social circles.
2. Shared interests and online activity
Facebook pays close attention to the pages and content you engage with on and off their platform. If you and another user are active in the same Facebook groups or interact with similar content, you may be suggested as friends.
This can happen even if you have no friends in common, as long as your online behavior demonstrates shared interests or values. For example, if you both actively like and comment on a local community Facebook group, this similarity in online activity makes you more likely to end up as suggestions for each other.
3. Shared networks and connections
Facebook’s friend recommendation algorithm analyzes extended networks and connections between people. Even if you have no directly mutual friends with someone, you may have overlapping networks or secondary connections.
For instance, if you went to the same university or have friends who went to the same high school, Facebook may determine you likely have shared connections. Degrees of separation, shared affiliations, and other extended networks make it more probable you could know each other.
4. Ad targeting
Facebook collects extensive data about users for ad targeting purposes. If you and another user share demographics, interests, behaviors, and other characteristics that make you ideal audiences for similar ads, you may show up as suggestions.
The ad targeting profiles Facebook creates go beyond your own activity on their platforms. They also incorporate data from third-party sites, apps, and offline sources. So you may be suggested based solely on shared traits ideal for certain types of advertising.
5. Random chance
With over 2 billion monthly active users on Facebook, there is always a possibility you’ll see random friend recommendations now and then. While Facebook’s algorithm is sophisticated, it cannot account for every potential connection or similarity between billions of users.
Occasionally, you may even get suggestions for people with nothing apparently in common with you. Facebook’s algorithm simply makes its best guess based on available data, which can sometimes result in random outliers.
6. Mutual friends you can’t see
In some cases, you and another user may actually have mutual friends, but their friendship is not visible to you. This can happen when a mutual friend has their friend list set to private.
Facebook can still analyze these invisible mutual connections as part of its friend recommendations algorithm. So you may be suggested friends who appear to have no mutuals, but do in reality.
7. Friends of friends
Even if you don’t have any direct mutual friends with someone, you may both be connected to the same group one degree removed. These “friends of friends” relationships are still considered by Facebook’s algorithm.
For example, you may be suggested a friend of someone you went to college with 10 years ago, because you share that extended network. So while not a direct mutual friend, your connection to the same group makes you more likely to show up for each other.
8. Friends of a friend of a friend
Facebook’s friend recommendations can consider even more extended networks by looking at “friends of friends of friends.” Even if you are three degrees removed from someone, you may still appear as a suggestion if you share enough of the same broader connections.
These types of distant recommendations happen when networks overlap and enough patterns emerge from the algorithm’s analysis. But from your perspective, it may seem totally random at first glance.
9. Friend requests you ignored
If someone sent you a friend request that you ignored or dismissed, Facebook may still continue suggesting them. This is because from their perspective, they clearly want to connect with you for some reason.
Facebook’s algorithm picks up on these one-way expressions of interest. Even if you passed on the request, you may keep appearing as a recommendation until they remove you as a suggested friend as well.
10. Friends you’ve removed or blocked
Similarly, Facebook may resurface people you’ve previously blocked or removed as friends. Since you had a connection at one point, their algorithm may continue trying to reconnect you based on that prior relationship.
So if you removed an old coworker as a friend, they could still show up as a suggestion. Facebook’s algorithm doesn’t necessarily know why you dissolved the friendship, so it may guess you’d want to reconnect.
11. Messenger connections
If you are connected with someone on Facebook Messenger who is not your Facebook friend, they may appear as a suggestion. This is because Facebook can see you have an established chat relationship.
Having someone’s phone number or communicating frequently through Messenger makes it more probable you would want to be Facebook friends as well. So these Messenger-only connections often parlay into friend recommendations.
12. Dating app connections
If you connect your Facebook account to a dating app like Tinder, it can inform friend recommendations. For example, if you match with someone on a dating app who also has a Facebook account, they may start appearing as a suggested friend.
Facebook picks up on these types of overlaps in online activity and social graphs. So your dating app matches may make their way into your Facebook recommended friends.
13. Work networks
If you list an employer on your Facebook profile, you may be recommended friends who work or have worked there. Facebook’s algorithm assumes colleagues at the same company likely know each other.
Similarly, if you went to the same college or have overlapping professional networks, Facebook may suggest you as friends. Shared affiliations, education, and work experiences make people more likely to know each other.
14. Groups and events
Participation in the same Facebook groups and events can also drive friend recommendations. For example, if you RSVP to a concert event that thousands of other people are also attending, some of them may show up as suggestions.
The same goes for active membership in local community groups or fan groups around books, TV shows, sports teams, etc. Shared participation indicates overlapping interests.
15. Linked devices and accounts
Facebook gathers data from your activity across any devices and accounts linked to it. If you access Facebook from a shared computer or have your Instagram or Messenger linked, it may inform friend suggestions.
For instance, a family member you see regularly may not be your Facebook friend. But if you both log into Facebook from the same household computer, you’re more likely to get suggested.
16. Contacts uploaded to Facebook
If you’ve given Facebook permission to access your contact list from your smartphone, it can match you with friends who also uploaded your info. Even if you don’t have any Facebook mutuals, your shared phone contacts make you more likely to get suggested.
Uploading your contacts essentially gives Facebook a broader view of your extended social network. People you’ve exchanged numbers with then become fair game as recommendations.
17. Friends of exes or former friends
Even if you are no longer directly connected to someone on Facebook, their friends may still show up as suggestions. For example, if you dated someone briefly or were college roommates, your ex’s or former roommate’s current friends could be recommended.
Facebook’s algorithm focuses on social proximity. So even though a direct connection dissolved, extended networks still matter and may drive indirect friend suggestions.
18. Friends who have become inactive on Facebook
If you were once Facebook friends with someone who has since become inactive or rarely logs in anymore, their friends may still show up as suggestions. Facebook’s algorithm doesn’t necessarily recognize that someone has gone inactive on the platform.
So your suggestions may reflect friendships and mutuals that have lapsed over time. Inactive friends can still drive recommendations until they formally close their accounts.
19. Friends you’ve unfollowed
If you “unfollow” a current Facebook friend so their posts no longer show up in your News Feed, their friends may still get suggested to you. Unfollowing only mutes someone’s updates – you remain connected as friends.
So Facebook’s algorithm still picks up on these active friendships even if you don’t see the person’s posts anymore. Their friends can still show up as recommendations.
20. People you “poked” years ago
Facebook’s “poke” feature has outlived its usefulness, but years ago it was a popular way to flirt or get someone’s attention. If you poked someone back in the day, they may still resurface years later as a friend recommendation.
Poking indicated a degree of interest or engagement.Facebook’s algorithm has a long memory, so those old pokes from a decade ago can still influence suggestions today.
Conclusion
Facebook’s friend recommendations are powered by a complex machine learning algorithm that analyzes billions of data points. While the results may seem random or irrelevant sometimes, the suggestions are based on identified patterns and connections between people on and off the platform.
Shared locations, interests, networks, online activity, and real-world experiences are all factors. So don’t be surprised if you get suggestions for people you have no obvious mutual friends with. Facebook’s algorithm sees connective tissue you may have missed.
Next time you notice one of these “mystery friends,” think about the many potential digital and real-world touch points Facebook could be picking up on. Their algorithm aims to create new social encounters – even if the connection isn’t immediately clear.