There are a total of 58 counties in the state of California. Among them, Butte County is the oldest one (established in 1850) while Imperial County is the youngest (established in 1907). With population of 10,163,507, Los Angeles County is the most populated. The biggest county by land area is San Bernardino County (1853 km2) and the smallest is San Francisco (122 km2). Below please see all California counties which are listed in alphabetical order.
- Alameda County, CA
- Alpine County, CA
- Amador County, CA
- Butte County, CA
- Calaveras County, CA
- Colusa County, CA
- Contra Costa County, CA
- Del Norte County, CA
- El Dorado County, CA
- Fresno County, CA
- Glenn County, CA
- Humboldt County, CA
- Imperial County, CA
- Inyo County, CA
- Kern County, CA
- Kings County, CA
- Lake County, CA
- Lassen County, CA
- Los Angeles County, CA
- Madera County, CA
- Marin County, CA
- Mariposa County, CA
- Mendocino County, CA
- Merced County, CA
- Modoc County, CA
- Mono County, CA
- Monterey County, CA
- Napa County, CA
- Nevada County, CA
- Orange County, CA
- Placer County, CA
- Plumas County, CA
- Riverside County, CA
- Sacramento County, CA
- San Benito County, CA
- San Bernardino County, CA
- San Diego County, CA
- San Francisco County, CA
- San Joaquin County, CA
- San Luis Opispo County, CA
- San Mateo County, CA
- Santa Barbara County, CA
- Santa Clara County, CA
- Santa Cruz County, CA
- Shasta County, CA
- Sierra County, CA
- Siskiyou County, CA
- Solano County, CA
- Sonoma County, CA
- Stanislaus County, CA
- Sutter County, CA
- Tehama County, CA
- Toulumne County, CA
- Trinity County, CA
- Tulare County, CA
- Ventura County, CA
- Yolo County, CA
- Yuba County, CA
Map of California Counties
