California 2020 Census Total Population By County

The total population of California from the 2020 Census was 39,538,223, based on data from the US Census Bureau.

Los Angeles County was the most populated county (10,014,009), followed by San Diego County (3,298,634), and then Orange County (3,186,989). On the other hand, the 3 counties that were least populated include: Alpine County (1,204), Sierra County (3,236), and Modoc County (8,700).

You can also see this information for other states and also for the US by state.

Hover over or click on the counties to see the number and percentage of California population that lives in each county. 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 also see the population by county for the different racial groups as well as the different ethnicities in California.