Clayton is located in Contra costa county California with a geographic area of 3.8 square miles. The total population in Clayton is 11,585 with 49.4% male and 50.6% female. Children under age 5 represent 4.5% of the population, under age 18 equal 24.7% of the population and over age 65 is 15.3% of the population. The median household income is $153,607, per capita income is $65,693. There are a total of 4,010 housing units with 90.1% owner occupied. Education includes 7.4% of residents that are high school graduates and 63.6% with a bachelor's degree or higher. The average temperature in Clayton in the summer is 70 degrees, and in the winter 43 degrees.
