Key biscayne is located in Miami-Dade county Florida with a geographic area of 1.2 square miles. The total population in Key biscayne is 12,867 with 48.5% male and 51.5% female. Children under age 5 represent 5.6% of the population, under age 18 equal 31.5% of the population and over age 65 is 14.0% of the population. The median household income is $166,667, per capita income is $78,732. There are a total of 4,058 housing units with 69.3% owner occupied. Education includes 3.0% of residents that are high school graduates and 80.0% with a bachelor's degree or higher. The average temperature in Key biscayne in the summer is 80 degrees, and in the winter 56 degrees.