Data / Rankings / Population density / Counties in California

Counties in California by population density

San Francisco County had the highest population density of 58 counties in 2020, at 7,237.7 inhabitants per km². Alpine County had the lowest, at 0.6 inhabitants per km². The median was 42.7 inhabitants per km² and the figure for California was 97.9 inhabitants per km². Source: the U.S. Census Bureau.

Highest7,237.7San Francisco County
Lowest0.6Alpine County
Median42.758 counties
California97.9History

All counties, 2020

CSVChart (SVG)

San Francisco CountySan Francisco County: 7,237.7 inhabitants per km²7,237.7Orange CountyOrange County: 1,550.8 inhabitants per km²1,550.8Los Angeles CountyLos Angeles County: 950.6 inhabitants per km²950.6Alameda CountyAlameda County: 879.8 inhabitants per km²879.8San Mateo CountySan Mateo County: 656.4 inhabitants per km²656.4Sacramento CountySacramento County: 634.6 inhabitants per km²634.6Contra Costa CountyContra Costa County: 628.1 inhabitants per km²628.1Santa Clara CountySanta Clara County: 577.6 inhabitants per km²577.6San Diego CountySan Diego County: 302.7 inhabitants per km²302.7Santa Cruz CountySanta Cruz County: 235.7 inhabitants per km²235.7San Joaquin CountySan Joaquin County: 216.5 inhabitants per km²216.5Solano CountySolano County: 212.8 inhabitants per km²212.8Marin CountyMarin County: 194 inhabitants per km²194Ventura CountyVentura County: 177 inhabitants per km²177Stanislaus CountyStanislaus County: 142.9 inhabitants per km²142.9Riverside CountyRiverside County: 129.8 inhabitants per km²129.8Sonoma CountySonoma County: 119.7 inhabitants per km²119.7Placer CountyPlacer County: 111.4 inhabitants per km²111.4Yolo CountyYolo County: 83 inhabitants per km²83Napa CountyNapa County: 70.6 inhabitants per km²70.6Fresno CountyFresno County: 65.4 inhabitants per km²65.4Sutter CountySutter County: 63.7 inhabitants per km²63.7Santa Barbara CountySanta Barbara County: 63.3 inhabitants per km²63.3Merced CountyMerced County: 56.4 inhabitants per km²56.4Monterey CountyMonterey County: 51.8 inhabitants per km²51.8Yuba CountyYuba County: 50.1 inhabitants per km²50.1Butte CountyButte County: 49.6 inhabitants per km²49.6El Dorado CountyEl Dorado County: 43.2 inhabitants per km²43.2Kern CountyKern County: 43 inhabitants per km²43Kings CountyKings County: 42.4 inhabitants per km²42.4San Bernardino CountySan Bernardino County: 42 inhabitants per km²42Nevada CountyNevada County: 41.2 inhabitants per km²41.2Tulare CountyTulare County: 37.9 inhabitants per km²37.9San Luis Obispo CountySan Luis Obispo County: 33 inhabitants per km²33Madera CountyMadera County: 28.3 inhabitants per km²28.3Amador CountyAmador County: 26.3 inhabitants per km²26.3Lake CountyLake County: 21 inhabitants per km²21Shasta CountyShasta County: 18.6 inhabitants per km²18.6San Benito CountySan Benito County: 17.9 inhabitants per km²17.9Calaveras CountyCalaveras County: 17.2 inhabitants per km²17.2Imperial CountyImperial County: 16.6 inhabitants per km²16.6Humboldt CountyHumboldt County: 14.7 inhabitants per km²14.7Del Norte CountyDel Norte County: 10.6 inhabitants per km²10.6Mendocino CountyMendocino County: 10.1 inhabitants per km²10.1Tuolumne CountyTuolumne County: 9.6 inhabitants per km²9.6Tehama CountyTehama County: 8.6 inhabitants per km²8.6Glenn CountyGlenn County: 8.5 inhabitants per km²8.5Colusa CountyColusa County: 7.3 inhabitants per km²7.3Mariposa CountyMariposa County: 4.6 inhabitants per km²4.6Plumas CountyPlumas County: 3 inhabitants per km²3Lassen CountyLassen County: 2.8 inhabitants per km²2.8Siskiyou CountySiskiyou County: 2.7 inhabitants per km²2.7Trinity CountyTrinity County: 2 inhabitants per km²2Mono CountyMono County: 1.7 inhabitants per km²1.7Sierra CountySierra County: 1.3 inhabitants per km²1.3Modoc CountyModoc County: 0.8 inhabitants per km²0.8Inyo CountyInyo County: 0.7 inhabitants per km²0.7Alpine CountyAlpine County: 0.6 inhabitants per km²0.6
inhabitants per km². Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2020
inhabitants per km²
1San Francisco County7,237.7
2Orange County1,550.8
3Los Angeles County950.6
4Alameda County879.8
5San Mateo County656.4
6Sacramento County634.6
7Contra Costa County628.1
8Santa Clara County577.6
9San Diego County302.7
10Santa Cruz County235.7
11San Joaquin County216.5
12Solano County212.8
13Marin County194
14Ventura County177
15Stanislaus County142.9
16Riverside County129.8
17Sonoma County119.7
18Placer County111.4
19Yolo County83
20Napa County70.6
21Fresno County65.4
22Sutter County63.7
23Santa Barbara County63.3
24Merced County56.4
25Monterey County51.8
26Yuba County50.1
27Butte County49.6
28El Dorado County43.2
29Kern County43
30Kings County42.4
31San Bernardino County42
32Nevada County41.2
33Tulare County37.9
34San Luis Obispo County33
35Madera County28.3
36Amador County26.3
37Lake County21
38Shasta County18.6
39San Benito County17.9
40Calaveras County17.2
41Imperial County16.6
42Humboldt County14.7
43Del Norte County10.6
44Mendocino County10.1
45Tuolumne County9.6
46Tehama County8.6
47Glenn County8.5
48Colusa County7.3
49Mariposa County4.6
50Plumas County3
51Lassen County2.8
52Siskiyou County2.7
53Trinity County2
54Mono County1.7
55Sierra County1.3
56Modoc County0.8
57Inyo County0.7
58Alpine County0.6

Other periods

About this ranking

Resident population divided by land area in km². World Bank figures use mid-year population and land area excluding inland water.

United States: Census Bureau population estimates for 1 July divided by land area (water excluded) from the latest Census Gazetteer files. US tables often give people per square mile; multiply persons per km² by 2.59 to compare.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Population Estimates Program resident population on 1 July divided by land area from the latest Census Gazetteer files, persons per km². https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-09.

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Questions

Which county has the highest population density?

San Francisco County, with 7,237.7 inhabitants per km² in 2020, according to the U.S. Census Bureau.

Which county has the lowest population density?

Alpine County, with 0.6 inhabitants per km² in 2020.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Population Estimates Program resident population on 1 July divided by land area from the latest Census Gazetteer files, persons per km². Retrieved 2026-10-09.

Population density: other rankings

Counties in California: more rankings