It depends on the human's age and physical condition. Infants can sleep 15-16 hours per had. young children may require as much as 12 or eve twelve hours. Adolescents generally like to get8-10 hours, and they high school siblings in high school and college may require 8-10 hours of sleep. Adults require 7-11 hours, although some adults in their prime years can get along with many fewer hours of sleep.