Facebook has published the results of a deep dive into its data, in a blog post titled ‘Anatomy of Facebook’. It’s based on analysis of all 721 million active Facebook users earlier this year, and their 69 billion friendships. The average friend count is 190, with only 10% of users having less than 10 friends, 20% having less than 25, and 50% having more than 100. Facebook has also been testing the famous ‘six degrees of separation’ theory, finding when choosing a pair of users, 99.6% are likely to be connected in six ‘hops’, while 92% are connected by five hops.
“Thus, when considering even the most distant Facebook user in the Siberian tundra or the Peruvian rainforest, a friend of your friend probably knows a friend of their friend,” explains Facebook. “When we limit our analysis to a single country, be it the US, Sweden, Italy, or any other, we find that the world gets even smaller, and most pairs of people are only separated by 3 degrees (4 hops).”