🇺🇸 Oakley is a city in Contra Costa County, California, United States. It is within the nine-county San Francisco Bay Area. Oakley was incorporated in 1999, making it the newest incorporated city in Contra Costa County.
Oakley has a population of over 43,991 people. Oakley also forms part of the wider Contra Costa County which has a population of over 1,165,927 people. It is also a part of the larger San Francisco Bay area.