Fleming island is located in Clay county Florida with a geographic area of 15.8 square miles. The total population in Fleming island is 30,582 with 48.3% male and 51.7% female. Children under age 5 represent 4.5% of the population, under age 18 equal 20.9% of the population and over age 65 is 20.1% of the population. The median household income is $101,685, per capita income is $43,869. There are a total of 11,093 housing units with 86.1% owner occupied. Education includes 14.9% of residents that are high school graduates and 51.2% with a bachelor's degree or higher. The average temperature in Fleming island in the summer is 80 degrees, and in the winter 56 degrees.