Louisville is located in Boulder county Colorado with a geographic area of 8.0 square miles. The total population in Louisville is 19,342 with 49.9% male and 50.1% female. Children under age 5 represent 5.2% of the population, under age 18 equal 24.3% of the population and over age 65 is 13.6% of the population. The median household income is $116,073, per capita income is $56,720. There are a total of 7,439 housing units with 72.0% owner occupied. Education includes 6.6% of residents that are high school graduates and 72.8% with a bachelor's degree or higher. The average temperature in Louisville in the summer is 69 degrees, and in the winter 29 degrees.