Olney is located in Montgomery county Maryland with a geographic area of 16.2 square miles. The total population in Olney is 35,350 with 50.0% male and 50.0% female. Children under age 5 represent 5.3% of the population, under age 18 equal 24.0% of the population and over age 65 is 16.2% of the population. The median household income is $149,155, per capita income is $56,115. There are a total of 11,727 housing units with 88.9% owner occupied. Education includes 8.7% of residents that are high school graduates and 68.2% with a bachelor's degree or higher. The average temperature in Olney in the summer is 74 degrees, and in the winter 37 degrees.