SmogRank / Countries / United States / California

Most polluted cities in California, United States

100 measured cities ranked by PM2.5, last 7 days. Worst: Calexico at 30.7 µg/m³, #75 in the world.

#	City	µg/m³
1	Calexico California	30.7
2	Los Angeles California	14.1
3	Jurupa Valley California	14.1
4	Clovis California	13.3
5	Riverside California	13.2
6	Fontana California	12.5
7	Hanford California	12.4
8	Whittier California	12.1
9	Hawthorne low-cost sensorsCalifornia	11.8
10	Fresno California	11.7
11	Compton California	11.5
12	San Diego California	11.4
13	Chula Vista California	11.2
14	Carson low-cost sensorsCalifornia	11.0
15	Inglewood low-cost sensorsCalifornia	10.7
16	Corcoran California	10.6
17	Santa Monica low-cost sensorsCalifornia	10.6
18	El Cajon California	10.2
19	Porterville California	10.2
20	Glendora California	10.1
21	Mission Viejo California	10.1
22	Oceanside California	10.1
23	Burbank California	10.0
24	Merced California	10.0
25	Tulare low-cost sensorsCalifornia	9.9
26	Anaheim California	9.7
27	Lomita low-cost sensorsCalifornia	9.7
28	Bakersfield California	9.5
29	Pasadena low-cost sensorsCalifornia	9.5
30	Madera California	9.4
31	Torrance low-cost sensorsCalifornia	9.4
32	Long Beach California	9.1
33	Poway California	9.1
34	San Jose California	9.1
35	Thousand Oaks California	9.0
36	Arroyo Grande California	8.8
37	Lake Elsinore California	8.8
38	San Leandro California	8.7
39	Salinas California	8.6
40	Agoura low-cost sensorsCalifornia	8.5
41	Santa Cruz California	8.5
42	Turlock California	8.4
43	Manteca California	8.1
44	Orcutt California	8.0
45	San Francisco California	8.0
46	Yuba City California	8.0
47	Huntington Beach low-cost sensorsCalifornia	7.9
48	Brawley California	7.8
49	Redwood City California	7.8
50	Arden-Arcade California	7.8
51	Vallejo California	7.7
52	Oakland California	7.6
53	Livermore California	7.5
54	Santa Clarita California	7.5
55	Prunedale low-cost sensorsCalifornia	7.4
56	Elk Grove low-cost sensorsCalifornia	7.3
57	Gilroy California	7.3
58	Stockton California	7.3
59	Concord California	6.9
60	Nipomo California	6.9
61	Oxnard California	6.9
62	Temecula California	6.8
63	Galt California	6.7
64	Simi Valley California	6.6
65	Sacramento California	6.4
66	South Lake Tahoe California	6.4
67	South San Francisco low-cost sensorsCalifornia	6.4
68	Victorville California	6.4
69	Banning California	6.3
70	Davis California	6.3
71	Live Oak low-cost sensorsCalifornia	6.3
72	La Crescenta-Montrose low-cost sensorsCalifornia	6.3
73	Hollister California	6.1
74	Fillmore California	6.0
75	Florin low-cost sensorsCalifornia	6.0
76	San Rafael California	6.0
77	Seaside low-cost sensorsCalifornia	6.0
78	Lincoln California	5.9
79	Delano low-cost sensorsCalifornia	5.8
80	El Centro California	5.8
81	Watsonville low-cost sensorsCalifornia	5.8
82	Goleta low-cost sensorsCalifornia	5.6
83	Los Banos low-cost sensorsCalifornia	5.5
84	Tracy California	5.5
85	Ukiah California	5.5
86	Santa Rosa California	5.3
87	Atascadero California	5.1
88	Ridgecrest California	5.0
89	Encinitas low-cost sensorsCalifornia	4.9
90	Redding California	4.9
91	Chico California	4.8
92	Truckee California	4.8
93	Windsor low-cost sensorsCalifornia	4.8
94	Indio California	4.6
95	Paradise California	4.6
96	Lancaster California	4.4
97	Lompoc California	4.2
98	Palo Alto low-cost sensorsCalifornia	4.1
99	Folsom California	3.8
100	Vacaville California	3.0

Good 0–9.0Moderate 9.1+Unhealthy for sensitive groups 35.5+Unhealthy 55.5+Very unhealthy 125.5+Hazardous 225.5+No data

Estimated: cities without a monitor

California cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City	7-day estimate	Band
Santa Ana estimated	≈ 8 µg/m³	Good
Irvine estimated	≈ 8 µg/m³	Good
Fremont estimated	≈ 9 µg/m³	Moderate
San Bernardino estimated	≈ 9 µg/m³	Good
Moreno Valley estimated	≈ 9 µg/m³	Good
Glendale estimated	≈ 12 µg/m³	Moderate
Garden Grove estimated	≈ 8 µg/m³	Good
Rancho Cucamonga estimated	≈ 12 µg/m³	Moderate
Corona estimated	≈ 11 µg/m³	Moderate
Palmdale estimated	≈ 6 µg/m³	Good
Hayward estimated	≈ 10 µg/m³	Moderate
Sunnyvale estimated	≈ 9 µg/m³	Good
Pomona estimated	≈ 10 µg/m³	Moderate
Escondido estimated	≈ 11 µg/m³	Moderate
Valencia estimated	≈ 7 µg/m³	Good
Orange estimated	≈ 8 µg/m³	Good
Fullerton estimated	≈ 12 µg/m³	Moderate
East Los Angeles estimated	≈ 11 µg/m³	Moderate
Santa Clara estimated	≈ 9 µg/m³	Good
El Monte estimated	≈ 11 µg/m³	Moderate
Carlsbad estimated	≈ 11 µg/m³	Moderate
Downey estimated	≈ 11 µg/m³	Moderate
Costa Mesa estimated	≈ 8 µg/m³	Good
Fairfield estimated	≈ 6 µg/m³	Good
Antioch estimated	≈ 9 µg/m³	Good
Murrieta estimated	≈ 10 µg/m³	Moderate
West Covina estimated	≈ 12 µg/m³	Moderate
Norwalk estimated	≈ 12 µg/m³	Moderate
Daly City estimated	≈ 7 µg/m³	Good
Santa Maria estimated	≈ 8 µg/m³	Good
San Mateo estimated	≈ 7 µg/m³	Good
Rialto estimated	≈ 9 µg/m³	Good
Vista estimated	≈ 11 µg/m³	Moderate
Ventura estimated	≈ 6 µg/m³	Good
South Gate estimated	≈ 12 µg/m³	Moderate
Hesperia estimated	≈ 5 µg/m³	Good
San Marcos estimated	≈ 11 µg/m³	Moderate
Westminster estimated	≈ 8 µg/m³	Good
Santa Barbara estimated	≈ 5 µg/m³	Good
Menifee estimated	≈ 10 µg/m³	Moderate

Updated 2026-10-01 10:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.