California Population By County in 2010

Updated on January 29, 2024.

Based on the US Census Vintage data estimates, in 2010, the population of California was 37,319,550. Among all California counties, Los Angeles had the highest population (9,821,647), followed by San Diego (3,103,260), and Orange (3,016,376). Alpine was the least populated county (1,161).

Hover over or click on the counties in the map below to see the populations. The data can also be found in a table below. You can use the table to sort, filter, and explore the data further.

You can see similar information for other states and by state for the United States.

See this for other years:
California Population By County in 2010
California Population By County in 2010
Items per page:
0 of 0
County Population % of State Population
Alameda 1512997 4.05
Alpine 1161 0.00
Amador 37883 0.10
Butte 219951 0.59
Calaveras 45467 0.12
Colusa 21435 0.06
Contra Costa 1052516 2.82
Del Norte 28568 0.08
El Dorado 181161 0.49
Fresno 932011 2.50
Glenn 28125 0.08
Humboldt 135010 0.36
Imperial 174704 0.47
Inyo 18503 0.05
Kern 841365 2.25
Kings 152342 0.41
Lake 64736 0.17
Lassen 34828 0.09
Los Angeles 9821647 26.32
Madera 151006 0.41
Marin 252906 0.68
Mariposa 18302 0.05
Mendocino 87796 0.24
Merced 256709 0.69
Modoc 9698 0.03
Mono 14256 0.04
Monterey 416358 1.12
Napa 136752 0.37
Nevada 98795 0.27
Orange 3016376 8.08
Placer 350007 0.94
Plumas 19915 0.05
Riverside 2201562 5.90
Sacramento 1421381 3.81
San Benito 55544 0.15
San Bernardino 2040803 5.47
San Diego 3103260 8.32
San Francisco 805519 2.16
San Joaquin 687115 1.84
San Luis Obispo 269800 0.72
San Mateo 719948 1.93
Santa Barbara 424218 1.14
Santa Clara 1786001 4.79
Santa Cruz 263174 0.71
Shasta 177277 0.48
Sierra 3220 0.01
Siskiyou 44941 0.12
Solano 413963 1.11
Sonoma 484675 1.30
Stanislaus 515137 1.38
Sutter 94742 0.25
Tehama 63562 0.17
Trinity 13755 0.04
Tulare 442953 1.19
Tuolumne 55164 0.15
Ventura 825144 2.21
Yolo 201061 0.54
Yuba 72345 0.19