Air quality · ZIP 90405
Air quality in Santa Monica, CA
In 2025, Los Angeles County, California — the county ZIP 90405 is in — had a median daily AQI of 74, which EPA rates Moderate. Of 365 days with a reading, 39 were Good, 228 Moderate, 66 Unhealthy for Sensitive Groups and 32 Unhealthy or worse. This is EPA's annual county summary, not today's air.
Los Angeles County, California · 2025 annual summary
Median AQI 74 — Moderate
Air quality is acceptable. However, there may be a risk for some people, particularly those unusually sensitive to air pollution.
- Good days
- 39
- Moderate days
- 228
- Unhealthy for sensitive groups
- 66
- Unhealthy+ days
- 32
- Max AQI
- 201
- 90th percentile AQI
- 147
This is a county-level ANNUAL SUMMARY for 2025, not a live current reading. For today's air quality, check a real-time monitor at airnow.gov. Categories follow EPA's official AQI breakpoints.
Next step for your own home
What this page shows
The 2025 annual EPA Air Quality System summary for this ZIP's county — shown above.
Source & refresh
EPA Air Quality System (AQS), annual county summary. The figures are EPA's 2025 annual county summary. EPA publishes one summary a year, so this is not today's air. Primary source →
Limitations specific to this source
This is a county-level ANNUAL SUMMARY, not a live current reading and not an address-level measurement — for today's AQI, EPA's real-time AirNow feed is the correct source (not yet federated here). Not every county operates an EPA monitor; absence of data for a ZIP's county means no 2025 EPA reading exists, not that air is good.
California context
Wildfire (WUI), seismic, water-supply variability
California carries the highest concentrated WUI wildfire risk in the US per USFS WHP, with FAIR Plan + non-renewal pressure intensifying since 2017 fires. FEMA NFHL coverage is strong; drinking-water systems vary from large urban (LADWP, EBMUD) to small disadvantaged community systems flagged in EPA SDWIS. Radon risk is mostly Zone 2-3.
See California state page for the full state-level rollup across all 12 dimensions.
Read more on air quality
Editorial deep-dives explaining the source data, its limits, and how to read it.
EPA AQI categories explained — what 0–50 Good through 301–500 Hazardous mean
Plain-English guide to the six EPA Air Quality Index categories: 0–50 Good, 51–100 Moderate, 101–150 Unhealthy for Sensitive Groups, 151–200 Unhealthy, 201–300 Very Unhealthy, 301–500 Hazardous — what each level means and who is at risk.
AQI explained — what 50, 100, 150 actually mean for your lungs
Plain-English guide to the EPA Air Quality Index (AQI) and the 6 categories from Good to Hazardous. When to take precautions and which pollutants matter.
Wildfire Hazard Potential — what the USFS scale means and how to defend your home
Plain-English guide to the USDA Forest Service's Wildfire Hazard Potential 1–5 scale, how to read your community's risk, and concrete home-defense measures.
AirNow + wildfire smoke — when AQI is a real-time tool
How EPA AirNow handles real-time wildfire smoke, what the colors mean during fire season, and where AirNow leaves gaps you should know about.
The other dimensions for ZIP 90405
Air quality is one of twelve public-records dimensions zipradar indexes per address. See the ZIP 90405 index for the other eleven — each with its own regulator, source and link:
All dimensions for Santa Monica, CA →Frequently asked questions
What is the air quality for ZIP 90405?
Los Angeles County, California (which covers ZIP 90405) had a 2025 median AQI of 74 — Moderate, per EPA's Air Quality System. Over the year: 39 Good days, 228 Moderate, 66 Unhealthy for Sensitive Groups. This is a county-level ANNUAL SUMMARY for 2025, not a live current reading. For today's air quality, check a real-time monitor at airnow.gov. Categories follow EPA's official AQI breakpoints.
Where does the air quality data come from?
Source: EPA Air Quality System (AQS), annual county summary. The figures are EPA's 2025 annual county summary. EPA publishes one summary a year, so this is not today's air. The original is at https://aqs.epa.gov/aqsweb/airdata/download_files.html.
What are the limitations of air quality data?
This is a county-level ANNUAL SUMMARY, not a live current reading and not an address-level measurement — for today's AQI, EPA's real-time AirNow feed is the correct source (not yet federated here). Not every county operates an EPA monitor; absence of data for a ZIP's county means no 2025 EPA reading exists, not that air is good.
Is ZIP 90405 (Santa Monica) data current?
zipradar last checked this page against the source on 2026-09-24. The figures are EPA's 2025 annual county summary. EPA publishes one summary a year, so this is not today's air. The ZIP 90405 overview at /zip/90405/ lists the other topics zipradar covers for this ZIP.