XFN, or XHTML Friends Network, is a simple way to define relationships between people on the web using HTML link types. By adding specific rel values to links, you describe how you know another person in a machine-readable and privacy-aware manner.
This approach is widely adopted in blogging platforms and social tools to express connections such as friendship, contact, or professional ties without exposing sensitive details unnecessarily. The following sections explore the main relationship types, practical implementation, and how XFN can fit into a modern identity strategy.
| rel Value | Meaning | Typical Use Case | Privacy Signal |
|---|---|---|---|
| friend | Mutual friendship | Linking to a close contact's profile | Public acknowledgment of friendship |
| met | You have met in person | Conference or event networking | Signals a real-world connection |
| colleague | Professional relation | Co-worker or partner on a project | Work context without detailed role |
| acquaintance | Known but not close | Casual contacts from groups or events | Lower intimacy, general awareness |
| co-worker | Current employment relation | Linking to a teammate on company site | Professional affiliation |
Understanding Common XFN Relationship Types
Mutual and One-Way Connections
XFN includes both mutual and one-way relationship indicators. A mutual friend link implies a confirmed, reciprocal connection, while a met or acquaintance link may reflect a one-sided acknowledgment. Clearly choosing the right rel value helps systems and readers interpret the nature of the link reliably.
Implementing XFN on Personal and Corporate Sites
Adding rel Values to Anchor Tags
To use XFN, add rel="xfn-value" to an tag that points to another person's profile. For example, Friend Name signals a friendly relationship. You can combine multiple values separated by spaces to describe complex connections accurately.
Privacy and Audience Considerations for XFN
Signaling Intent Without Over Disclosure
XFN allows you to acknowledge relationships publicly while keeping personal details private. You link to a profile page without exposing email addresses, phone numbers, or location data. This balance makes XFN useful on corporate sites and personal blogs where controlled disclosure is important.
Best Practices for Managing XFN Links
- Only link to profiles that the person has agreed to be referenced.
- Use accurate rel values that reflect the real relationship.
- Combine XFN with other identity standards only when they add value.
- Test links to ensure they resolve correctly and respect robots.txt.
- Update or remove links promptly when relationships change.
Evolving Identity Practices Around XFN
As platforms integrate decentralized identity and verifiable credentials, XFN style relationships may inform portable proof of connection. Current implementations remain lightweight, but the patterns established by XFN support clearer, more respectful linking practices in future identity systems.
FAQ
Reader questions
Can XFN be used for professional networking on a corporate website?
Yes, XFN is suitable for professional networking on corporate sites. Use values such as colleague or co-worker to indicate working relationships while maintaining control over what information is exposed through the linked profile.
Do search engines use XFN values for ranking pages?
Search engines generally treat XFN links as regular hyperlinks with additional semantic meaning. They may use these links for understanding entity relationships in structured data, but XFN alone is not a direct ranking factor.
Should I combine XFN with other microformat or schema markup?
You can combine XFN with other microformats or schema types to enrich how profiles are interpreted. Ensure the combined markup is consistent and does not create conflicting signals about identity or relationship types.
What happens if the linked profile changes or becomes unavailable?
If the linked profile is removed or updated, verify that the relationship still reflects reality. Update or remove the XFN link to prevent broken references and to keep the signal accurate for users and systems that inspect the markup.