El cajon is located in San diego county California with a geographic area of 14.5 square miles. The total population in El cajon is 103,249 with 49.1% male and 50.9% female. Children under age 5 represent 7.5% of the population, under age 18 equal 25.5% of the population and over age 65 is 12.7% of the population. The median household income is $56,367, per capita income is $25,940. There are a total of 33,496 housing units with 41.9% owner occupied. Education includes 25.0% of residents that are high school graduates and 24.5% with a bachelor's degree or higher. The average temperature in El cajon in the summer is 74 degrees, and in the winter 43 degrees.