Naperville is located in Will county Illinois with a geographic area of 39.1 square miles. The total population in Naperville is 147,734 with 49.2% male and 50.8% female. Children under age 5 represent 5.8% of the population, under age 18 equal 25.3% of the population and over age 65 is 13.0% of the population. The median household income is $127,648, per capita income is $58,075. There are a total of 52,648 housing units with 74.3% owner occupied. Education includes 6.6% of residents that are high school graduates and 73.1% with a bachelor's degree or higher. The average temperature in Naperville in the summer is 72 degrees, and in the winter 27 degrees.