Thousand Oaks, California Air Quality
Thousand Oaks air quality today — the AQI, the main pollutant, and whether it’s safe to exercise outside right now
Thousand Oaks, CA · Air quality right now
The air quality index in Thousand Oaks, CA is 48 (Good) right now — safe for outdoor activity.
Is it safe to be outside in Thousand Oaks today?
AQI 48 Yes — air quality is Good
Air is clean — great for outdoor activity.Main pollutant: PM2.5Observed 2:00 AM PDT
Pollutants right now
- PM2.510 µg/m³Main pollutantfine particles — smoke, exhaust, soot
- PM1014 µg/m³coarse particles — dust, pollen, ash
- Ozone72 µg/m³smog — builds on hot, sunny days
- NO₂7.8 µg/m³nitrogen dioxide — traffic, combustion
ExerciseOK to run — no air-quality limits on outdoor exercise.
How to read Thousand Oaks’s air quality
Guides: The AQI Scale, Explained · Air Quality Alerts, Decoded · How to Read a Wildfire Smoke Map · Why Wildfire Smoke Travels 1,000 Miles.
Air quality over time in Thousand Oaks
Across the EPA’s county records from 2020 to 2025, Thousand Oaks’s cleanest year was 2023 (median AQI 46) and its most polluted was 2021 (median AQI 53); the typical (median) day has trended cleaner since 2020.
| Year | Median AQI | Unhealthy+ | Main pollutant | USG | Moderate | Good |
|---|---|---|---|---|---|---|
| 2020 | 50 | 5 | Ozone | 21 | 155 | 185 |
| 2021 | 53 | 0 | Ozone | 10 | 198 | 157 |
| 2022 | 52 | 0 | Ozone | 11 | 183 | 171 |
| 2023 | 46 | 0 | Ozone | 12 | 133 | 220 |
| 2024 | 50 | 1 | Ozone | 14 | 160 | 191 |
| 2025 | 50 | 0 | Ozone | 8 | 167 | 190 |
“USG” is Unhealthy for Sensitive Groups (AQI 101–150); “Unhealthy+” combines the Unhealthy, Very Unhealthy, and Hazardous days. In 2024 the EPA tightened the annual fine-particle (PM2.5) standard to 9 µg/m³ from the previous 12 µg/m³, so counties near the old limit read worse against the new one. Source: EPA AQS annual summaries, 2020–2025.
Frequently asked
- What was the worst year for air quality in Thousand Oaks?
- In the EPA's 2020–2025 county records, 2020 had the most days above AQI 100: 26 days (21 Unhealthy for Sensitive Groups, 5 Unhealthy or worse). The highest median AQI came in 2021 (53; 2020's was 50).
- How many unhealthy air days does Thousand Oaks have?
- Across 2020–2025, 4% of the days reported for Thousand Oaks's county had an AQI above 100 (82 of 2192), about 14 days a year. 2025 had 8 days.
- What's the main air pollutant in Thousand Oaks?
- Ozone: it drove Thousand Oaks's county AQI on the most days in every year of the EPA's 2020–2025 records.