California county geography overview
California has 58 counties, which places it 27th among the 50 state and District of Columbia maps in this atlas when ordered by number of county-level units. Their combined 155,860.4 square miles of land place the state 3rd by mapped land area.
The average county-level area is 2,687 square miles, while the median is 1,536 square miles. The median is often the better description of a typical unit because one or two very large areas can pull the average upward. The five largest units together account for about 33% of the state’s mapped land area.
Largest and smallest California counties
San Bernardino County is the largest county-level unit by land area at 20,068.4 square miles. It represents about 13% of all mapped land in California. At the other end of the range, San Francisco County has 46.7 square miles of land.
Largest by land area
- San Bernardino County20,068.4 sq mi
- Inyo County10,197.3 sq mi
- Kern County8,134.7 sq mi
- Riverside County7,209 sq mi
- Siskiyou County6,278.8 sq mi
Smallest by land area
- San Francisco County46.7 sq mi
- Santa Cruz County445.1 sq mi
- San Mateo County448.6 sq mi
- Marin County520.1 sq mi
- Amador County594.6 sq mi
Rankings use land area rather than total area. This avoids making coastal or lake counties appear larger solely because their boundaries include extensive water.
Alphabetical list of California counties
The table is alphabetical, so it works as a name and FIPS-code reference rather than an area ranking. Every identifier begins with the California state FIPS prefix 06. Land and water figures are rounded to one decimal place.
58 county-level areas
Download county data / numbered map key (CSV)| No. | Name | FIPS code | Land area | Water area |
|---|---|---|---|---|
| 1 | Alameda County | 06001 | 737.5 sq mi | 83.7 sq mi |
| 2 | Alpine County | 06003 | 738.3 sq mi | 4.8 sq mi |
| 3 | Amador County | 06005 | 594.6 sq mi | 11.4 sq mi |
| 4 | Butte County | 06007 | 1,636.5 sq mi | 40.6 sq mi |
| 5 | Calaveras County | 06009 | 1,020 sq mi | 16.9 sq mi |
| 6 | Colusa County | 06011 | 1,150.6 sq mi | 5.7 sq mi |
| 7 | Contra Costa County | 06013 | 716.9 sq mi | 87 sq mi |
| 8 | Del Norte County | 06015 | 1,006.2 sq mi | 223.5 sq mi |
| 9 | El Dorado County | 06017 | 1,707.8 sq mi | 78.5 sq mi |
| 10 | Fresno County | 06019 | 5,958.6 sq mi | 52.8 sq mi |
| 11 | Glenn County | 06021 | 1,313.9 sq mi | 13 sq mi |
| 12 | Humboldt County | 06023 | 3,568 sq mi | 484.2 sq mi |
| 13 | Imperial County | 06025 | 4,175.5 sq mi | 305.1 sq mi |
| 14 | Inyo County | 06027 | 10,197.3 sq mi | 29.8 sq mi |
| 15 | Kern County | 06029 | 8,134.7 sq mi | 30.2 sq mi |
| 16 | Kings County | 06031 | 1,391 sq mi | 1.2 sq mi |
| 17 | Lake County | 06033 | 1,255.1 sq mi | 73 sq mi |
| 18 | Lassen County | 06035 | 4,541.4 sq mi | 178.7 sq mi |
| 19 | Los Angeles County | 06037 | 4,060.3 sq mi | 689.1 sq mi |
| 20 | Madera County | 06039 | 2,136.7 sq mi | 16.3 sq mi |
| 21 | Marin County | 06041 | 520.1 sq mi | 308 sq mi |
| 22 | Mariposa County | 06043 | 1,448.8 sq mi | 14 sq mi |
| 23 | Mendocino County | 06045 | 3,506.8 sq mi | 371.3 sq mi |
| 24 | Merced County | 06047 | 1,938 sq mi | 40.6 sq mi |
| 25 | Modoc County | 06049 | 3,948.2 sq mi | 255 sq mi |
| 26 | Mono County | 06051 | 3,048.9 sq mi | 82.9 sq mi |
| 27 | Monterey County | 06053 | 3,281.7 sq mi | 489.5 sq mi |
| 28 | Napa County | 06055 | 752 sq mi | 40.3 sq mi |
| 29 | Nevada County | 06057 | 957.8 sq mi | 16 sq mi |
| 30 | Orange County | 06059 | 793.2 sq mi | 156.5 sq mi |
| 31 | Placer County | 06061 | 1,407.4 sq mi | 94.8 sq mi |
| 32 | Plumas County | 06063 | 2,553.1 sq mi | 60.4 sq mi |
| 33 | Riverside County | 06065 | 7,209 sq mi | 93.7 sq mi |
| 34 | Sacramento County | 06067 | 965.4 sq mi | 29 sq mi |
| 35 | San Benito County | 06069 | 1,388.7 sq mi | 1.8 sq mi |
| 36 | San Bernardino County | 06071 | 20,068.4 sq mi | 37.2 sq mi |
| 37 | San Diego County | 06073 | 4,210.9 sq mi | 315 sq mi |
| 38 | San Francisco County | 06075 | 46.7 sq mi | 185.2 sq mi |
| 39 | San Joaquin County | 06077 | 1,392.3 sq mi | 34.3 sq mi |
| 40 | San Luis Obispo County | 06079 | 3,300.8 sq mi | 314.9 sq mi |
| 41 | San Mateo County | 06081 | 448.6 sq mi | 292.4 sq mi |
| 42 | Santa Barbara County | 06083 | 2,733.9 sq mi | 1,053.7 sq mi |
| 43 | Santa Clara County | 06085 | 1,291.1 sq mi | 13 sq mi |
| 44 | Santa Cruz County | 06087 | 445.1 sq mi | 162.1 sq mi |
| 45 | Shasta County | 06089 | 3,775.7 sq mi | 71.7 sq mi |
| 46 | Sierra County | 06091 | 953.2 sq mi | 9 sq mi |
| 47 | Siskiyou County | 06093 | 6,278.8 sq mi | 69.2 sq mi |
| 48 | Solano County | 06095 | 821.7 sq mi | 84.4 sq mi |
| 49 | Sonoma County | 06097 | 1,575.3 sq mi | 192 sq mi |
| 50 | Stanislaus County | 06099 | 1,496.2 sq mi | 17.9 sq mi |
| 51 | Sutter County | 06101 | 602.7 sq mi | 5.7 sq mi |
| 52 | Tehama County | 06103 | 2,949.1 sq mi | 13 sq mi |
| 53 | Trinity County | 06105 | 3,179.3 sq mi | 28.3 sq mi |
| 54 | Tulare County | 06107 | 4,823.9 sq mi | 14.4 sq mi |
| 55 | Tuolumne County | 06109 | 2,220.9 sq mi | 53.5 sq mi |
| 56 | Ventura County | 06111 | 1,840.8 sq mi | 365.8 sq mi |
| 57 | Yolo County | 06113 | 1,013 sq mi | 8.8 sq mi |
| 58 | Yuba County | 06115 | 632 sq mi | 12 sq mi |
How to read and use this map
County lines are administrative boundaries, not postal routes. A mailing address can use a city name associated with a neighboring area, and ZIP codes can cross county lines. When you need to identify a county for an address, confirm it with an official geocoder or local government source.
For classroom or planning use, download a PDF from the controls above. Labelled exports use numbered callouts for crowded areas; numbered quiz maps match the alphabetical county list. SVG files keep the boundary lines sharp at larger paper sizes.
Frequently asked questions
How many counties are in California?
California has 58 counties in the U.S. Census Bureau’s 2025 cartographic boundary file.
Can I print this California county map?
Yes. Choose Download / print and select PDF for a landscape Letter page, PNG for an image, or SVG for editable vector artwork. Because the map is SVG, its boundary lines stay sharp when scaled.
What is the largest county in California?
San Bernardino County is the largest by land area in this dataset at 20,068.4 square miles. This is an area ranking, not a population ranking.
What is the smallest county in California?
San Francisco County is the smallest by land area in this dataset at 46.7 square miles.
Are these legal survey boundaries?
No. This is a generalized reference map. Property, parcel, election, and legal boundary questions should be checked with the relevant state or local agency.
Map source
U.S. Census Bureau, 2025 Cartographic Boundary File, Counties, 1:5,000,000. Land and water area fields are supplied in the same file and converted from square meters to square miles. Accessed September 27, 2026.