Facebook’s friend suggestion algorithm is designed to connect you with people you may know on the platform. When Facebook suggests a new friend to you, it does not automatically send that person a suggestion to add you as a friend as well. The friend suggestion system is asymmetrical – if Facebook suggests Person A send a friend request to Person B, it does not necessarily suggest to Person B that they send a request to Person A. There are a few key factors that go into how Facebook determines which friend suggestions to show you:
How Facebook’s Friend Suggestion Algorithm Works
Here are some of the main signals Facebook uses to generate friend suggestions:
- Friends of friends – If you have a lot of friends in common with someone, Facebook will suggest them.
- School and work networks – Facebook looks at what schools or companies you have in common with people.
- Location history – If you and another person have checked into the same places, you may be suggested.
- Groups and events – Being a member of the same groups or attending the same events can trigger a suggestion.
- Likes and interests – Having similar tastes, hobbies, entertainment interests can lead to a suggestion.
In addition to these factors, Facebook also utilizes machine learning models trained on social graph data to predict connections between people on the platform. The friend recommendation models get smarter over time based on new examples of friend connections.
Why Friend Suggestions Are Asymmetrical
When Facebook’s algorithm suggests Person A send a friend request to Person B, there are a few reasons why Person B may not receive the reciprocal suggestion:
- Person B’s privacy settings may preclude friend suggestions.
- Person B may already have too many friend requests pending.
- Person B may have already declined a friend request from Person A.
- There may not be enough signal in Person B’s data to justify suggesting Person A.
- Facebook’s models may have predicted Person B would not want to connect with Person A.
Essentially, Facebook attempts to only show you friend suggestions that its systems believe have a reasonably high chance of resulting in actual friend connections. The cues can be subtle and difficult to decipher from the outside.
When You Get a Suggestion
Now that we’ve covered how Facebook’s friend suggestion algorithm works at a high level, let’s walk through what happens when you receive a new suggestion:
The Friend Suggestion Appears
When you log into Facebook, you may see a few new friend suggestions waiting for you. They are typically displayed on the right rail of your News Feed. The suggestion will display the person’s name, profile photo, mutual friends (if any), and common interests/groups/networks you share.
You Have a Few Options
When you receive a friend suggestion, you can take one of the following actions:
- Send a friend request by clicking the “Add Friend” button.
- Click “See More About [Person’s Name]” to view their full profile and learn more before deciding.
- Select “I Don’t Know This Person” if you believe the suggestion is irrelevant.
- Click the “X” icon to dismiss the suggestion.
If you do not take any action, the suggestion will eventually time out and disappear from your page after a few days.
They May Not Get a Reciprocal Suggestion
Importantly, if you send a friend request to someone that Facebook suggested, they will not necessarily receive the reverse suggestion to add you as a friend. Unless there are strong signals in their profile and social graph data indicating you would be a relevant friend for them, Facebook’s algorithm likely will not prompt them to add you.
When You Accept a Suggestion
If you decide to send a friend request to someone suggested by Facebook, here is an overview of what happens next:
Your Request is Pending
Once you click the “Add Friend” button on a suggestion, the person will receive a notification of your friend request. On your end, the request will display as “Pending” under your Friends menu.
They Can Accept, Ignore, or Decline
The person has the following options for responding to your friend request:
- Accept – They add you as a friend, and you will both see each other in your respective Friends lists.
- Ignore – They take no action on the request. It remains in a “Pending” state until they accept, decline, or the request expires.
- Decline – They actively decline the request, and you will no longer see them under Pending requests.
If the person ignores the friend request, it will eventually expire and disappear after a set time period determined by Facebook.
No Guarantee of a Reciprocal Suggestion
Again, it’s important to note that even if someone accepts your friend request that originated from a Facebook suggestion, they will not necessarily receive the reverse friend suggestion for you. Unless the signals align properly, Facebook’s algorithm will not prompt them to take that action. The system is intentionally asymmetrical.
Other Ways to Become Friends
While friend suggestions represent one way of potentially connecting with someone on Facebook, there are other paths as well:
Search for Their Profile
You can always search for someone’s name or profile directly through Facebook’s search bar. If you find their profile this way, you can send a friend request that they can accept or decline. This does not rely on Facebook’s recommendation algorithm.
Mutual Friend Introductions
One classic way people connect on Facebook is when a mutual friend introduces two people by tagging them in a post or comment. Either person can then initiate a friend request through this common connection.
Networking Through Groups
Joining common interest groups and interacting with members is another way to form potential friendships organically. If you hit it off in a group, friending each other can be a natural next step.
Real-Life Interactions
Of course, many Facebook friends originate from in-person interactions, such as meeting at a party or through a workplace. Swapping Facebook info remains a common way for people to connect after meeting.
Facebook’s Explanation
Here is an excerpt from an official Facebook Help Center article explaining how their friend recommendations work:
We generate friend recommendations by looking at things like mutual friends, work and education information, networks you’re part of, contacts you’ve imported and other factors.
Importantly, just because you see a recommendation doesn’t necessarily mean that person will see a recommendation to become friends with you. The friend recommendations you see are based on your privacy settings, your networks and other factors.
You’re in control. If you don’t want to be suggested as a friend connection, you can update your privacy settings. To help ensure you don’t appear as a suggestion for someone, you can remove your contacts, change the audiences who can see your friends list, review tags you’re associated with or limit the audience for posts you’ve been tagged in.
So in summary, Facebook acknowledges that friend recommendations are not reciprocated automatically both due to algorithmic factors as well as user privacy settings.
Research Studies on Facebook’s Algorithm
Data scientists have conducted studies analyzing the patterns and accuracy of Facebook’s friend recommendation models:
Mining Social Media Data
In a 2020 study published in Applied Sciences, researchers performed social network analysis on Facebook friend connections and recommendations. They found friend suggestions were most strongly correlated with common friends, social clusters, and profile attributes like workplace and education. The system did not appear to weigh all factors equally.
Evaluating Suggestion Accuracy
A 2016 study in the International Journal of Hybrid Information Technology tested friend recommendations on sample Facebook user data. They found the algorithm’s precision ranged from 44% to 66% accuracy depending on the data inputs used in the system. Recommendations based on shared connections in groups and events were most accurate.
Analyzing Link Prediction
A 2015 paper in Physica A: Statistical Mechanics and its Applications examined how graph theory and link prediction methods could model the formation of new friend connections of Facebook. The researchers found that features like Adamic-Adar index and preferential attachment provided the most predictive power compared to other techniques.
Critiques of the Algorithm
Some analyses have pointed out potential issues with Facebook’s approach. A 2014 study in Social Network Analysis and Mining noted friend recommendations can create “filter bubbles” by reinforcing homogeneity and not suggesting diverse connections. Other work has examined how
recommendations can reveal sensitive user data against their wishes when connections are made public.
Frequently Asked Questions
Here are answers to some common questions about how Facebook’s friend suggestion algorithm works:
Does Facebook notify a person when you view their profile?
No, Facebook does not send any notification when you view someone’s profile. You can access any public profile on Facebook without the user being alerted. They have no way to know you visited their profile unless you send a friend request or interact directly with them in some way. Simply viewing a profile leaves no trace.
Can you see who views your Facebook profile?
Facebook does not have a built-in feature that shows you who has viewed your profile. There are some third-party browser extensions that claim to reveal profile visitors, but Facebook does not authorize or recommend using them. Any service offering to show your profile visitors should be treated with skepticism, as the data they provide is unlikely to be accurate or sanctioned by Facebook.
Why do I see Facebook friend recommendations from people I don’t know?
In some cases, you may see friend recommendations from people with whom you have no obvious connection. This can happen when Facebook’s algorithm detects some subtle link between you and that person based on interests, networks, location history, or other signals. Even a weak signal can sometimes trigger a suggestion. However, the odds of you friending a total stranger are low in most cases.
Can you recommend a friend on Facebook without them getting notified?
No, there is no way to privately recommend someone as a friend without triggering a notification to them. As soon as you click the “Add Friend” button on someone’s profile, they will receive an alert about your pending friend request. Facebook designed the friending system to be transparent in this way. If you do not want someone to be notified, it’s best not to send the request.
How many friend recommendations does Facebook show at once?
Facebook typically displays 3-4 friend recommendations at a time in the right side panel of your News Feed. However, if you access the full Recommendations section under Friends, you can view many more suggestions, typically around 20-30 at once. The number will vary based on how many potential recommendations Facebook’s algorithm was able to generate for your account.
Conclusion
In summary, when Facebook suggests a new potential friend, the recommendation algorithm does not work bilaterally. If you receive a suggestion to add Friend A, it does not mean that Friend A will necessarily receive the reverse prompt to connect with you. A number of factors determine which recommendations you see, and why those may differ from what other people see. While not a perfect system, Facebook’s friend suggestions can provide a starting point for making new social connections on the platform if used wisely by discerning users. But the onus remains on individuals to evaluate the relevance of each recommendation themselves.