You Can Only Have 150 Friends - Dunbar's Numbers Explained

Trust and informal coordination become harder as groups outgrow people’s capacity to maintain recognizable relationships. Organizations can resist that shift by creating stable physical or administrative units near human social limits.

Human social cognition can maintain only a limited number of stable, particular relationships—roughly 150 on average. Beyond that scale, people are increasingly compressed into roles, stereotypes, and tribal signals.

Social capacity is partly a cognitive capacity: maintaining a larger group requires tracking more people and the relationships among them. Across species, larger brains are associated with larger social groups.

Online networks turn people you might have understood as neighbors into standards, numbers, and fragments. Without the context that supports empathy and restraint, stereotyping and outrage become easier.

Your inner circle has a capacity limit: adding a new intimate relationship often displaces attention and closeness from someone already inside it.

Keep teams small enough that members can track one another’s work and coordinate directly. Once that visibility breaks down, divide the work into smaller units with explicit interfaces between them.

Relationships form nested layers: roughly 5 in an inner circle, 15 close friends, 50 good friends, and 150 people whose lives you can meaningfully track. As each layer expands, intimacy and detailed knowledge thin out.