Data / Rankings / Population density / Counties in California

Counties in California by population density, 2025

San Francisco County had the highest population density of 58 counties in 2025, at 6,832 inhabitants per km². Alpine County had the lowest, at 0.5 inhabitants per km². The median was 43.2 inhabitants per km² and the figure for California was 97.5 inhabitants per km². Source: the U.S. Census Bureau.

Highest6,832San Francisco County
Lowest0.5Alpine County
Median43.258 counties
California97.5History

All counties, 2025

CSVChart (SVG)

San Francisco CountySan Francisco County: 6,832 inhabitants per km²6,832Orange CountyOrange County: 1,533 inhabitants per km²1,533Los Angeles CountyLos Angeles County: 921.9 inhabitants per km²921.9Alameda CountyAlameda County: 856.9 inhabitants per km²856.9Sacramento CountySacramento County: 647.3 inhabitants per km²647.3San Mateo CountySan Mateo County: 640 inhabitants per km²640Contra Costa CountyContra Costa County: 630.2 inhabitants per km²630.2Santa Clara CountySanta Clara County: 572.5 inhabitants per km²572.5San Diego CountySan Diego County: 301 inhabitants per km²301San Joaquin CountySan Joaquin County: 228.5 inhabitants per km²228.5Santa Cruz CountySanta Cruz County: 224.5 inhabitants per km²224.5Solano CountySolano County: 214 inhabitants per km²214Marin CountyMarin County: 188.3 inhabitants per km²188.3Ventura CountyVentura County: 174.3 inhabitants per km²174.3Stanislaus CountyStanislaus County: 143.9 inhabitants per km²143.9Riverside CountyRiverside County: 136.3 inhabitants per km²136.3Placer CountyPlacer County: 121.3 inhabitants per km²121.3Sonoma CountySonoma County: 119.2 inhabitants per km²119.2Yolo CountyYolo County: 85.5 inhabitants per km²85.5Napa CountyNapa County: 68.3 inhabitants per km²68.3Fresno CountyFresno County: 67.1 inhabitants per km²67.1Sutter CountySutter County: 63.3 inhabitants per km²63.3Santa Barbara CountySanta Barbara County: 62.4 inhabitants per km²62.4Merced CountyMerced County: 59.2 inhabitants per km²59.2Yuba CountyYuba County: 54.2 inhabitants per km²54.2Monterey CountyMonterey County: 51 inhabitants per km²51Butte CountyButte County: 49.4 inhabitants per km²49.4Kern CountyKern County: 44 inhabitants per km²44El Dorado CountyEl Dorado County: 43.5 inhabitants per km²43.5Kings CountyKings County: 42.8 inhabitants per km²42.8San Bernardino CountySan Bernardino County: 42.8 inhabitants per km²42.8Nevada CountyNevada County: 41.1 inhabitants per km²41.1Tulare CountyTulare County: 38.8 inhabitants per km²38.8San Luis Obispo CountySan Luis Obispo County: 33 inhabitants per km²33Madera CountyMadera County: 30.3 inhabitants per km²30.3Amador CountyAmador County: 27.2 inhabitants per km²27.2Lake CountyLake County: 20.8 inhabitants per km²20.8San Benito CountySan Benito County: 19.5 inhabitants per km²19.5Shasta CountyShasta County: 18.6 inhabitants per km²18.6Calaveras CountyCalaveras County: 17.6 inhabitants per km²17.6Imperial CountyImperial County: 16.8 inhabitants per km²16.8Humboldt CountyHumboldt County: 14.2 inhabitants per km²14.2Del Norte CountyDel Norte County: 10.1 inhabitants per km²10.1Mendocino CountyMendocino County: 9.7 inhabitants per km²9.7Tuolumne CountyTuolumne County: 9.2 inhabitants per km²9.2Tehama CountyTehama County: 8.5 inhabitants per km²8.5Glenn CountyGlenn County: 8.3 inhabitants per km²8.3Colusa CountyColusa County: 7.3 inhabitants per km²7.3Mariposa CountyMariposa County: 4.5 inhabitants per km²4.5Plumas CountyPlumas County: 2.8 inhabitants per km²2.8Siskiyou CountySiskiyou County: 2.6 inhabitants per km²2.6Lassen CountyLassen County: 2.4 inhabitants per km²2.4Trinity CountyTrinity County: 1.9 inhabitants per km²1.9Mono CountyMono County: 1.6 inhabitants per km²1.6Sierra 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: 0.5 inhabitants per km²0.5
inhabitants per km². Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2025
inhabitants per km²		Change on 2024
1San Francisco County6,832+0.6%
2Orange County1,533-0.3%
3Los Angeles County921.9-0.6%
4Alameda County856.90%
5Sacramento County647.3+0.5%
6San Mateo County640+0.4%
7Contra Costa County630.20%
8Santa Clara County572.5+0.3%
9San Diego County301-0.2%
10San Joaquin County228.5+0.8%
11Santa Cruz County224.5-1%
12Solano County214+0.1%
13Marin County188.3-0.8%
14Ventura County174.3-0.3%
15Stanislaus County143.9+0.1%
16Riverside County136.3+0.6%
17Placer County121.3+1.8%
18Sonoma County119.2+0.2%
19Yolo County85.5+0.5%
20Napa County68.3-0.1%
21Fresno County67.1+0.2%
22Sutter County63.3-0.1%
23Santa Barbara County62.4-0.2%
24Merced County59.2+0.2%
25Yuba County54.2+1.4%
26Monterey County51+0.1%
27Butte County49.4+0.3%
28Kern County44+0.3%
29El Dorado County43.5-0%
30Kings County42.8+0.1%
31San Bernardino County42.8+0.2%
32Nevada County41.1-0.2%
33Tulare County38.8+0.3%
34San Luis Obispo County33+0.1%
35Madera County30.3+1.1%
36Amador County27.2-0.2%
37Lake County20.8-0.2%
38San Benito County19.5+1.4%
39Shasta County18.6+0.1%
40Calaveras County17.6+0.2%
41Imperial County16.8-0.7%
42Humboldt County14.2-0.5%
43Del Norte County10.1-2%
44Mendocino County9.7-0.9%
45Tuolumne County9.2-1.9%
46Tehama County8.5-0.2%
47Glenn County8.3-0.6%
48Colusa County7.3-0.8%
49Mariposa County4.5-0.2%
50Plumas County2.8-1%
51Siskiyou County2.6-1.1%
52Lassen County2.4-1.7%
53Trinity County1.9+0.2%
54Mono County1.6-1.4%
55Sierra County1.3-0.7%
56Modoc County0.8-1.3%
57Inyo County0.7-0.7%
58Alpine County0.5-4%

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 6,832 inhabitants per km² in 2025, according to the U.S. Census Bureau.

Which county has the lowest population density?

Alpine County, with 0.5 inhabitants per km² in 2025.

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