Leave it to sociologists to come up with such a number. Actually kind of interesting that they found that it takes 50 hours with someone to consider them a casual friend. Up to 200 hours is what it takes to have that best friend status.
This study says it takes:
40-60 hours to be a casual friend
80-100 hours to make a real
200 hours to be a close friend
A new study published in the Journal of Social and Personal Relationships recently calculated that, on average, it takes about 50 hours of time with someone before you consider them a casual friend, 90 hours before you become real friends, and about 200 hours to become close friends.