The average size of an adult human brain is about 1,300 to 1,400 cubic centimeters, which is roughly the size of ten tennis balls. The average weight of the adult human brain is about 3 pounds or 1,300 to 1,400 grams
. The average brain weight of adult males is about 1,336 grams, and for adult females, it is about 1,198 grams
