According to the United States Census, Contra Costa County, California's estimated population is 1,162,547, up 0.26 percent over the previous year. Contra Costa County is the tenth largest county in the state of California. The number of people in 2010 was 1,052,540, up 10.45 percent from the previous year. Contra Costa County has an area of 804 square miles (2,080 km2), with 716 square miles (1,850 km2) of land and 88 square miles (230 km2) of water, according to the US Census Bureau.

The bayside alluvial plain, the Oakland Hills-Berkeley Hills, various inland valleys, and Mount Diablo, an isolated 3,849-foot (1,173 m) upthrust peak at the north end of the Diablo Range of hills, dominate Contra Costa County's physical topography. Mount Diablo's top is the origin of Mount Diablo Meridian and BaseLine, which is used to survey much of California and western Nevada.

Contra Costa County's real estate market is diverse, with many homes for sale and properties available for rent or purchase. The median price for homes sold in Contra Costa County was $600,000 as of September 2018, while the median rent was $2,200 per month as of March 2019. In addition, Contra Costa County has many great amenities, including golf courses and country clubs, parks and open spaces, schools, hospitals and medical centers, shopping malls and outlets, restaurants, theaters and concert venues.
Education
There are seven schools and 458 students registered in the Contra Costa County Office of Education. The minority enrollment rate in the district is 70%. Furthermore, 69.2% of kids are economically challenged.

The Contra Costa County Office of Education serves a student population of 24 percent, White, 28.4% Black, 6.6 percent Asian or Asian/Pacific Islander, 35.8% Hispanic/Latino, 0.4 percent American Indian, and 0.7 percent Native Hawaiian or other Pacific Islander. Additionally, 4.1 percent of pupils are of two or more races, and 0% have not stated their race or ethnicity.

Climate/Weather
Contra Costa County's average annual high temperature is 30.8°C (87.4°F), with August 28 being the hottest day on average. The county's average annual low temperature is 3.4°C (38.1°F), with December 31 being the coldest day on average. February and January are the wettest months in Contra Costa County.