Facebook suggests friends based on mutual friends, contacts, groups, schools, workplaces, and activity.
Signals used
- Mutual friends.
- Contacts you uploaded.
- Same school, workplace or city.
- Shared groups and events.
- People who visited your profile or follow the same pages.
Controls
You can hide suggestions, remove contact uploads and limit who can find you in Settings.
Privacy tip
Review Privacy Settings, then Who can look you up.
Main data sources
Facebook’s “People You May Know” feature looks at connections and activity. Meta’s help pages list signals such as mutual friends, networks (school, workplace, city), contacts uploaded from your phone, and being in the same groups, events or tagged photos.
Contact uploading
If you or another person uploaded a contact list, the platform can match phone numbers and email addresses to profiles. This is how you may see a suggestion for someone you only know by phone number, even when you have no mutual friends.
Graph analysis
The system assigns higher likelihood to people who share many mutual friends. In large social networks, the number of mutual connections is one of the strongest predictors of a real world acquaintance.
Location data
Location sharing can contribute if you enable it, for example when two people often use the same Wi-Fi network or are at the same events.
Why suggestions can surprise you
Suggestions can appear for people who looked at your profile or who share something you have not noticed, such as an old workplace, a school class or a mutual contact in someone else’s address book.
Controls
- Go to Settings and privacy, Settings, Upload contacts (Meta Contacts Importer) and turn off continuous uploading, then delete uploaded contacts.
- Remove a suggestion with the X button.
- Limit who can find you by phone number or email under Privacy settings.
- Turn off location history on the phone.
Legal background
In 2013 and 2018, journalists and regulators raised concerns about people appearing in suggestions in sensitive contexts, and Meta has since changed some controls. Privacy rules such as the GDPR give users in Europe rights to access and delete data.
Data sources used for suggestions
The “People You May Know” feature on Facebook suggests people based on mutual friends, shared groups, events, school and workplace listings, tagged photos and contact information that you or others have uploaded. If someone uploads their phone contacts to Facebook, you may be recommended to anyone who has your phone number or email saved. The system analyzes the social graph, which means the web of connections between accounts, and mutual friends are the strongest signal. Meta has said it does not use location data for this feature, though suggestions can still seem uncanny.
Privacy controls and legal background
In Settings, you can turn off contact uploading and delete uploaded contacts, limit who can find you with your phone number or email, and adjust profile visibility. In July 2019, the Federal Trade Commission announced a 5 billion USD penalty against Facebook over privacy violations, and it required new privacy oversight. You cannot fully opt out of being suggested to others, but you can reduce how discoverable you are. Review your friends list occasionally and ignore requests from strangers.
Based on data from the Federal Trade Commission and Meta Help Center
