Think about your closest friends—the people you call daily, share your secrets with, and text at 2 a.m. when you need a favor or some emotional support. How many people are you picturing? One? Three? Eight? If you're like most people, you probably answered between three and five. (And apparently, the TV show Friends got it just right.)

As Lifehacker points out, British anthropologist Dr. Robin Dunbar was the first researcher to discover that people could really only maintain relationships with an average of 148 people throughout their lifetime. The brain can only process so much social information, and relationships with about 150 friends, family members, and acquaintances seems to be the cut-off point. This might explain why comedian Tom Segura’s joke about not having the mental energy to meet new people got so many laughs while filming his 2014 Netflix special Completely Normal in Minneapolis. During his set, he suggested, “Next time you’re at a bar or you’re just out walking around, and somebody goes, ‘Hey, man.’ Just go, ‘Nope. I’m all friended up.’”

Dunbar continued to study the subject of friendship, and in 2016, he and two other researchers identified “layers of friends” within the larger circle of 150 relationships. The team analyzed a mobile phone dataset and used the frequency of calls to indicate the closeness of relationships between callers. They found that as the number of friends in any given layer increases, the emotional closeness of those relationships decreases. In other words, the smallest layer generally contains three to five of your closest pals. The next layer overlaps and contains 10 additional people—or 15 people total, counting your five BFFs. The third layer has an additional 35 people, followed by a final layer with an additional 100.

It may come as a surprise that the makeup of these layers doesn’t differ significantly between introverts and extroverts, even though extroverts tend to have more friends overall. So if you have three to five true-blue friends, you're on target.

[h/t Lifehacker]