Los Angeles vs San Diego Air Quality Comparison

Which city has cleaner air right now, from the latest EPA AirNow AQI

As of September 16, 2026, Los Angeles, CA has cleaner air than San Diego, CAAQI 38 (Good) vs 54 (Moderate), a gap of 16 AQI points in the latest EPA AirNow observations. Lower AQI means cleaner air. Los Angeles's reading is driven by O3 and San Diego's by PM2.5.

Los Angeles, CA

Good

StateCalifornia
Dominant PollutantO3
CategoryGood

San Diego, CA

Moderate

StateCalifornia
Dominant PollutantPM2.5
CategoryModerate

Summary

Los Angeles has 16 points better air quality

Los Angeles has an AQI of 38 compared to 54

Our Pick

Extra Protection for San Diego Homes

Air quality in San Diego is moderate (AQI 54), with fine particles (PM2.5) the main concern. A True-HEPA purifier gives sensitive groups — kids, seniors and anyone with asthma or allergies — cleaner air indoors on days like today.

Large Room4.6(8,000+ ratings)
Coway AP-1512HH Mighty
True HEPA + carbon · CADR ~246 CFM · rooms up to 361 sq ft
True HEPA + carbon, high CADR — clears PM2.5 from most rooms fast, our all-round pick

Compare top-rated True-HEPA purifiers:

Large Room
Coway AP-1512HH Mighty
HEPA + Carbon
True HEPA + carbon · CADR ~246 CFM · rooms up to 361 sq ft
~$2304.6
Check Price on Amazon →
Editor's Pick
Levoit Vital 200S
True HEPA
True HEPA · washable pre-filter · rooms up to 1,875 sq ft
~$2004.6
Check Price on Amazon →
Budget Pick
Levoit Core 400S
True HEPA
True HEPA · CADR ~141 CFM · rooms up to 219 sq ft
~$1004.7
Check Price on Amazon →

Prices are approximate and subject to change. As an Amazon Associate, we earn from qualifying purchases at no extra cost to you.

5-Day Forecast Comparison

DayLos AngelesSan DiegoBetter
TodayAQI 50AQI 55Los Angeles