Skip to main content
AirHistory

New York, New York vs Los Angeles, California Air Quality

Side-by-side air quality comparison using 10 years of EPA monitoring data. New York, New York has the edge with an Air Quality Grade of B (70/100).

Reviewed by AirHistory Editorial Team · Updated
MetricNew York, New YorkLos Angeles, California
Air Quality GradeB (70/100)D (36/100)
Current Median AQI48 (Good)67 (Moderate)
5-Year Average AQI4475
10-Year Trend Improving (-4) Improving (-15)
Unhealthy Days/Year4100
Primary PollutantFine Particulate Matter (PM2.5)Fine Particulate Matter (PM2.5)

Side-by-Side Analysis

New York, New York outperforms Los Angeles, California on overall air quality with a Grade B (70/100) versus D (36/100). New York, New York's 5-year median AQI of 44 sits in the "Good" range, while Los Angeles, California averages 75 ("Moderate") — a 31-point gap that shows up consistently in year-over-year readings, not just in a single year.

Both cities are on improving trajectories — New York, New York at roughly 1.2 AQI/yr cleaner and Los Angeles, California at 0.9 AQI/yr cleaner. That mirrors the broader U.S. pattern of falling pollution as cleaner vehicles, cleaner power generation, and tighter emissions standards take effect.

What's in the Air

Both cities share the same dominant pollutant: Fine Particulate Matter (PM2.5). These cities' dominant issue is fine particulate matter — typically driven by combustion (vehicles, wildfire smoke, industry, residential wood burning). PM2.5 is the air pollutant most strongly linked to long-term cardiovascular and respiratory disease because the particles penetrate the bloodstream.

Health Implications

Over a 5-year window, New York, New York averages roughly 4 unhealthy air days per year (AQI above 100, where sensitive groups should limit outdoor exertion) versus 100 for Los Angeles, California. That 96-day gap matters most for residents with asthma, COPD, heart disease, or pregnancy — and for outdoor workers, who accumulate the most cumulative exposure. The city with fewer unhealthy days offers a meaningfully different baseline risk picture for sensitive populations. For long-term residents, the cleaner-air city is associated with measurably better outcomes on respiratory disease, cardiovascular events, and life expectancy — Harvard cohort research consistently finds 0.5 to 1.0 years of additional life expectancy for each 10-µg/m³ reduction in long-term PM2.5 exposure.

Frequently Asked Questions

New York, New York has better air quality with a Grade B (70/100) compared to Los Angeles, California's Grade D (36/100). New York, New York has a current median AQI of 48 and is improving over the past decade.

New York, New York averages 4 unhealthy air days per year (5-year average), while Los Angeles, California averages 100. Unhealthy days are those when AQI exceeds 100 and sensitive groups should limit outdoor activity.

New York, New York's primary pollutant is Fine Particulate Matter (PM2.5), while Los Angeles, California's is Fine Particulate Matter (PM2.5). Both cities share the same dominant pollutant.

Last updated:

Source: EPA Outdoor Air Quality Data, 2026.

The side-by-side above pulls the EPA Air Quality System data data for both New York, New York and Los Angeles, California. What follows is the interpretation — which specific axes carry the most weight for New York, New York versus Los Angeles, California, and which differences are large enough to influence a real decision.

Practical use of the comparison: read the data above, then drill into the individual New York, New York and Los Angeles, California detail pages for the underlying breakdown. A pairwise comparison answers the relative question; the per-entity pages answer the absolute question.