Demopolis is located in Marengo county Alabama with a geographic area of 17.7 square miles. The total population in Demopolis is 6,724 with 44.0% male and 56.0% female. Children under age 5 represent 7.5% of the population, under age 18 equal 23.5% of the population and over age 65 is 20.2% of the population. The median household income is $32,743, per capita income is $26,433. There are a total of 2,952 housing units with 55.3% owner occupied. Education includes 36.5% of residents that are high school graduates and 20.5% with a bachelor's degree or higher. The average temperature in Demopolis in the summer is 79 degrees, and in the winter 43 degrees.