Every year in the United States, tens of millions of Americans move to a new home. According to the U.S. Census Bureau, the bulk of these moves are motivated by personal circumstances, often relating to housing, family, or employment. But when it comes to deciding on a place to live, it can also be helpful to weigh other, less subjective factors.

As a means of gauging and comparing degrees of development between countries — beyond standard measures like gross domestic product and economic growth — the United Nations created the Human Development Index. By accounting for factors related to health and well-being, educational attainment, and standards of living, the HDI offers an assessment of overall quality of life at the individual level within a given geography.

When applied to communities within the United States, the core principles of the HDI reveal that some parts of the country are far better places to live than others.

Using an index inspired by the HDI, 24/7 Wall St. identified the best counties in California to live in. Counties are ranked on a combination of three measures – average life expectancy at birth, the share of adults with a bachelor’s degree or higher, and the poverty rate. Of the 57 counties in California with sufficient data, we ranked the 30 with the highest HDI score.

Across all of California, average life expectancy at birth is 81 years. Additionally, 12.1% of the population live below the poverty line and 35.9% of adults have a bachelor’s degree or higher. Of the 30 counties on this list, 13 compare favorably to the state as a whole in each of these metrics.

Among these 30 California counties, average life expectancy at birth ranges from 78.3 years to over 100. Meanwhile, poverty rates vary between 6.4% and 17.4%, and bachelor’s degree attainment rates range from about 20% to over 60%.

Data used to calculate rankings are from the U.S. Census Bureau’s 2022 American Community Survey and County Health Rankings & Roadmaps, a joint program of the Robert Wood Johnson Foundation and the University of Wisconsin Population Health Institute. All ACS data are five-year averages.

Why It Matters

Many of the most commonly cited economic indicators — including unemployment, GDP, and industrial output — are useful gauges of prosperity and productive capacity in a given area. But when it comes to measuring overall quality of life, any single metric inevitably falls short. To address these shortcomings, the HDI combines three key social and economic measures into a single index score, allowing for objective comparisons between communities across the United States.

30. Tuolumne County

• Avg. life expectancy at birth: 78.3 years
• Poverty rate: 11.4%
• Adults with a bachelor’s degree: 24.4%
• Median household income: $70,432
• Population: 54,993

29. Mariposa County

• Avg. life expectancy at birth: 80.6 years
• Poverty rate: 16.0%
• Adults with a bachelor’s degree: 28.9%
• Median household income: $60,021
• Population: 17,130

28. Sierra County

• Avg. life expectancy at birth: 81.0 years
• Poverty rate: 12.6%
• Adults with a bachelor’s degree: 23.9%
• Median household income: $61,108
• Population: 2,916

27. Riverside County

• Avg. life expectancy at birth: 80.0 years
• Poverty rate: 11.4%
• Adults with a bachelor’s degree: 24.1%
• Median household income: $84,505
• Population: 2,429,487

26. Amador County

• Avg. life expectancy at birth: 79.8 years
• Poverty rate: 7.8%
• Adults with a bachelor’s degree: 20.6%
• Median household income: $74,853
• Population: 40,577

25. Inyo County

• Avg. life expectancy at birth: 78.7 years
• Poverty rate: 11.9%
• Adults with a bachelor’s degree: 29.0%
• Median household income: $63,417
• Population: 18,829

24. Monterey County

• Avg. life expectancy at birth: 82.2 years
• Poverty rate: 12.3%
• Adults with a bachelor’s degree: 27.1%
• Median household income: $91,043
• Population: 437,609

23. Sacramento County

• Avg. life expectancy at birth: 79.2 years
• Poverty rate: 13.1%
• Adults with a bachelor’s degree: 32.6%
• Median household income: $84,010
• Population: 1,579,211

22. San Benito County

• Avg. life expectancy at birth: 81.9 years
• Poverty rate: 7.5%
• Adults with a bachelor’s degree: 22.0%
• Median household income: $104,451
• Population: 64,753

21. Solano County

• Avg. life expectancy at birth: 80.0 years
• Poverty rate: 9.0%
• Adults with a bachelor’s degree: 28.2%
• Median household income: $97,037
• Population: 450,995

20. Los Angeles County

• Avg. life expectancy at birth: 81.3 years
• Poverty rate: 13.7%
• Adults with a bachelor’s degree: 34.6%
• Median household income: $83,411
• Population: 9,936,690

19. Santa Barbara County

• Avg. life expectancy at birth: 81.8 years
• Poverty rate: 13.5%
• Adults with a bachelor’s degree: 35.7%
• Median household income: $92,332
• Population: 445,213

18. Yolo County

• Avg. life expectancy at birth: 81.5 years
• Poverty rate: 17.4%
• Adults with a bachelor’s degree: 43.3%
• Median household income: $85,097
• Population: 217,141

17. San Luis Obispo County

• Avg. life expectancy at birth: 81.8 years
• Poverty rate: 12.6%
• Adults with a bachelor’s degree: 38.0%
• Median household income: $90,158
• Population: 281,712

16. Ventura County

• Avg. life expectancy at birth: 82.3 years
• Poverty rate: 9.0%
• Adults with a bachelor’s degree: 34.7%
• Median household income: $102,141
• Population: 842,009

15. Nevada County

• Avg. life expectancy at birth: 80.8 years
• Poverty rate: 10.4%
• Adults with a bachelor’s degree: 38.8%
• Median household income: $79,395
• Population: 102,322

14. Sonoma County

• Avg. life expectancy at birth: 82.0 years
• Poverty rate: 8.9%
• Adults with a bachelor’s degree: 37.8%
• Median household income: $99,266
• Population: 488,436

13. El Dorado County

• Avg. life expectancy at birth: 81.9 years
• Poverty rate: 8.6%
• Adults with a bachelor’s degree: 38.0%
• Median household income: $99,246
• Population: 191,713

12. San Diego County

• Avg. life expectancy at birth: 81.8 years
• Poverty rate: 10.6%
• Adults with a bachelor’s degree: 41.0%
• Median household income: $96,974
• Population: 3,289,701

11. Napa County

• Avg. life expectancy at birth: 82.1 years
• Poverty rate: 7.9%
• Adults with a bachelor’s degree: 37.8%
• Median household income: $105,809
• Population: 137,384

10. Santa Cruz County

• Avg. life expectancy at birth: 82.7 years
• Poverty rate: 11.4%
• Adults with a bachelor’s degree: 42.5%
• Median household income: $104,409
• Population: 268,571

9. Orange County

• Avg. life expectancy at birth: 82.8 years
• Poverty rate: 9.7%
• Adults with a bachelor’s degree: 42.8%
• Median household income: $109,361
• Population: 3,175,227

8. Contra Costa County

• Avg. life expectancy at birth: 82.2 years
• Poverty rate: 8.3%
• Adults with a bachelor’s degree: 44.5%
• Median household income: $120,020
• Population: 1,162,648

7. Placer County

• Avg. life expectancy at birth: 82.3 years
• Poverty rate: 6.8%
• Adults with a bachelor’s degree: 42.4%
• Median household income: $109,375
• Population: 406,608

6. Alameda County

• Avg. life expectancy at birth: 82.8 years
• Poverty rate: 9.2%
• Adults with a bachelor’s degree: 50.9%
• Median household income: $122,488
• Population: 1,663,823

5. Mono County

• Avg. life expectancy at birth: >100 years
• Poverty rate: 11.3%
• Adults with a bachelor’s degree: 31.7%
• Median household income: $82,038
• Population: 13,219

4. San Francisco County

• Avg. life expectancy at birth: 83.7 years
• Poverty rate: 10.5%
• Adults with a bachelor’s degree: 59.8%
• Median household income: $136,689
• Population: 851,036

3. San Mateo County

• Avg. life expectancy at birth: 84.9 years
• Poverty rate: 6.4%
• Adults with a bachelor’s degree: 52.9%
• Median household income: $149,907
• Population: 754,250

2. Santa Clara County

• Avg. life expectancy at birth: 84.7 years
• Poverty rate: 6.9%
• Adults with a bachelor’s degree: 55.3%
• Median household income: $153,792
• Population: 1,916,831

1. Marin County

• Avg. life expectancy at birth: 85.3 years
• Poverty rate: 7.0%
• Adults with a bachelor’s degree: 61.1%
• Median household income: $142,019
• Population: 260,485

Rank	County	Avg. life expectancy at birth (yrs.)	Adults with a bachelor’s degree (%)	Poverty rate (%)	Population
1	Marin, California	85.3	61.1	7.0	260,485
2	Santa Clara, California	84.7	55.3	6.9	1,916,831
3	San Mateo, California	84.9	52.9	6.4	754,250
4	San Francisco, California	83.7	59.8	10.5	851,036
5	Mono, California	100+	31.7	11.3	13,219
6	Alameda, California	82.8	50.9	9.2	1,663,823
7	Placer, California	82.3	42.4	6.8	406,608
8	Contra Costa, California	82.2	44.5	8.3	1,162,648
9	Orange, California	82.8	42.8	9.7	3,175,227
10	Santa Cruz, California	82.7	42.5	11.4	268,571
11	Napa, California	82.1	37.8	7.9	137,384
12	San Diego, California	81.8	41.0	10.6	3,289,701
13	El Dorado, California	81.9	38.0	8.6	191,713
14	Sonoma, California	82.0	37.8	8.9	488,436
15	Nevada, California	80.8	38.8	10.4	102,322
16	Ventura, California	82.3	34.7	9.0	842,009
17	San Luis Obispo, California	81.8	38.0	12.6	281,712
18	Yolo, California	81.5	43.3	17.4	217,141
19	Santa Barbara, California	81.8	35.7	13.5	445,213
20	Los Angeles, California	81.3	34.6	13.7	9,936,690
21	Solano, California	80.0	28.2	9.0	450,995
22	San Benito, California	81.9	22.0	7.5	64,753
23	Sacramento, California	79.2	32.6	13.1	1,579,211
24	Monterey, California	82.2	27.1	12.3	437,609
25	Inyo, California	78.7	29.0	11.9	18,829
26	Amador, California	79.8	20.6	7.8	40,577
27	Riverside, California	80.0	24.1	11.4	2,429,487
28	Sierra, California	81.0	23.9	12.6	2,916
29	Mariposa, California	80.6	28.9	16.0	17,130
30	Tuolumne, California	78.3	24.4	11.4	54,993

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