Dunbar’s Number: The theory behind social circles

Dunbar’s Number suggests that the human brain can realistically only handle a limited number of social bonds or relationships. You can leverage this theory to your advantage in the workplace, maximizing efficiency and productivity. In this article, we will discuss how to apply Dunbar’s Number in the workplace to create a more effective social network.

Group of colleagues sitting around table

The theory explained

Humans naturally form social circles, with the size of those circles estimated to be somewhere between 100 and 250 people. This is commonly referred to as Dunbar's Number, named after British anthropologist Robin Dunbar, who first proposed the concept in 1992. Dunbar based his research on primates, observing the size of their social groups and extrapolating that same size to humans.

The theory states that humans can only maintain a certain number of meaningful relationships at any given time, which is largely determined by the size of their social network. To put it simply, the more people you know, the less deep of a connection you can form with each one. This is why it's important to focus on quality over quantity in the workplace.

Application in the workplace

Understanding Dunbar's Number can help managers, supervisors, and employees alike to better navigate today's work environment.

1. Building meaningful relationships

The theory suggest that strong professional networks can benefit your career by providing support and resources, as well as new ideas and creative solutions. To start building this network, focus on the five people you work closest with and make an effort to connect with them. This could involve anything from meeting up for lunch, attending team events together, having coffee or a casual conversation.

2. Determining team sizes

According to Dunbar's research, he proposed that the ideal size for a productive group lies between 5 and 150 members. This includes workers, supervisors and other stakeholders. Each size has its own advantages and disadvantages, so it is important to understand the dynamics of a group before deciding on what size works for you.

0-5 members

A team in this size is too small and can lead to the lack of motivation.

5 -15 members

5-15 members tend to work more efficiently, as each member can provide direct input and influence on the decision-making process. If a team grows larger than this number, it can lead to a lack of focus and direction.

15-50 members

This team is large enough to provide diversity and flexibility, but small enough for each individual to still have a voice.

50-150 members

At this point, the team size can become unmanageable and difficult to manage. A large number of members means there will be more collaboration and communication issues, making it increasingly difficult to reach consensus.

When working with a bigger team, try to divide the members into smaller, more manageable subteams. This will ensure that everyone has a chance to contribute and help make informed decisions.

3. Be aware of your social energy and limits

The Dunbar's Number theory also suggests that you should be aware of your own social energy and limits. It's important to recognize when you’re feeling overwhelmed and take the necessary steps to re-energize yourself, such as taking a break or participating in activities that make you feel good. People have different capacities for socializing, and it's important to respect your own limits so that you can maintain strong relationships with your coworkers without getting overwhelmed.


Though Dunbar's Number is a popular concept, there is still much debate around it. Many believe that the number is too low, and that it does not account for the potential for individuals to develop meaningful relationships with more than 150 people. Others point out that the size of a person's social circle can vary greatly depending on their lifestyle, career, and interests. As such, some suggest that the concept should not be seen as a hard limit, but rather an average that can vary from person to person.

Ultimately, Dunbar's Number is just one of many theories that can help in understanding the complexities of human relationships and social dynamics. While it can provide valuable insight, it should not be seen as a hard and fast rule. Instead, it should be used as a guideline on how to build meaningful relationships with colleagues.

What to take-away

  • Dunbar’s Number suggests that there is a limit to the number of meaningful relationships we can maintain at once, and that this limit lies somewhere between 5 to 150 people. Therefore, it’s important to focus on the quality of relationships, rather than quantity.
  • It’s also important to be aware of your own social energy limits, to ensure that you don’t become overwhelmed and exhausted.
  • Finally, while Dunbar’s Number can provide insight into relationships and social dynamics, it should not be seen as a hard and fast rule. Instead, it should be used to inform decisions about how best to build meaningful relationships with colleagues and teammates.

About me

Hi, I’m Lilian. I’m currently the head of a design team in a digital agency in Amsterdam and love to write about leadership and share tips based on my experience over the past couple of years.

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