Air Quality in Boulder, Colorado
49
Median AQI (2024)
154
Max AQI (2024)
→ stable
10-Year Trend
Ozone
Primary Pollutant
212
Good Days (2024)
9
Monitoring Stations
AQI Trend (Median)
Air Quality Days by Category
Annual Summary
| Year | Median AQI | Max AQI | Good Days | Moderate Days | Unhealthy Days | Ozone Days | PM2.5 Days |
|---|---|---|---|---|---|---|---|
| 2024 | 49 | 154 | 212 | 144 | 10 | 231 | 126 |
| 2023 | 50 | 181 | 192 | 167 | 6 | 272 | 93 |
| 2022 | 47 | 129 | 224 | 134 | 7 | 260 | 105 |
| 2021 | 52 | 160 | 154 | 176 | 35 | 228 | 136 |
| 2020 | 51 | 181 | 173 | 172 | 21 | 213 | 152 |
| 2019 | 50 | 119 | 192 | 168 | 5 | 234 | 131 |
| 2018 | 49 | 159 | 198 | 135 | 29 | 265 | 97 |
| 2017 | 46 | 149 | 233 | 113 | 11 | 320 | 37 |
| 2016 | 39 | 97 | 178 | 26 | 0 | 103 | 97 |
| 2015 | 44 | 129 | 253 | 105 | 7 | 327 | 37 |
Recent Daily AQI
| Date | AQI | Category | Primary Pollutant |
|---|---|---|---|
| Dec 31, 2024 | 32 | Good | Ozone |
| Dec 30, 2024 | 44 | Good | Ozone |
| Dec 29, 2024 | 40 | Good | Ozone |
| Dec 28, 2024 | 38 | Good | Ozone |
| Dec 27, 2024 | 44 | Good | Ozone |
| Dec 26, 2024 | 43 | Good | Ozone |
| Dec 25, 2024 | 43 | Good | PM2.5 |
| Dec 24, 2024 | 53 | Moderate | PM2.5 |
| Dec 23, 2024 | 52 | Moderate | PM2.5 |
| Dec 22, 2024 | 52 | Moderate | PM2.5 |
| Dec 21, 2024 | 56 | Moderate | PM2.5 |
| Dec 20, 2024 | 52 | Moderate | PM2.5 |
| Dec 19, 2024 | 45 | Good | Ozone |
| Dec 18, 2024 | 45 | Good | Ozone |
| Dec 17, 2024 | 45 | Good | Ozone |
| Dec 16, 2024 | 34 | Good | Ozone |
| Dec 15, 2024 | 50 | Good | Ozone |
| Dec 14, 2024 | 40 | Good | Ozone |
| Dec 13, 2024 | 43 | Good | Ozone |
| Dec 12, 2024 | 39 | Good | PM2.5 |
| Dec 11, 2024 | 44 | Good | Ozone |
| Dec 10, 2024 | 44 | Good | Ozone |
| Dec 9, 2024 | 37 | Good | Ozone |
| Dec 8, 2024 | 42 | Good | Ozone |
| Dec 7, 2024 | 54 | Moderate | PM2.5 |
| Dec 6, 2024 | 54 | Moderate | PM2.5 |
| Dec 5, 2024 | 52 | Moderate | PM2.5 |
| Dec 4, 2024 | 44 | Good | PM2.5 |
| Dec 3, 2024 | 49 | Good | PM2.5 |
| Dec 2, 2024 | 55 | Moderate | PM2.5 |
| Dec 1, 2024 | 46 | Good | PM2.5 |
| Nov 30, 2024 | 42 | Good | Ozone |
| Nov 29, 2024 | 45 | Good | Ozone |
| Nov 28, 2024 | 52 | Moderate | PM2.5 |
| Nov 27, 2024 | 35 | Good | Ozone |
| Nov 26, 2024 | 49 | Good | PM2.5 |
| Nov 25, 2024 | 39 | Good | PM2.5 |
| Nov 24, 2024 | 47 | Good | PM2.5 |
| Nov 23, 2024 | 62 | Moderate | PM2.5 |
| Nov 22, 2024 | 69 | Moderate | PM2.5 |
| Nov 21, 2024 | 61 | Moderate | PM2.5 |
| Nov 20, 2024 | 31 | Good | Ozone |
| Nov 19, 2024 | 41 | Good | Ozone |
| Nov 18, 2024 | 40 | Good | Ozone |
| Nov 17, 2024 | 41 | Good | Ozone |
| Nov 16, 2024 | 50 | Good | PM2.5 |
| Nov 15, 2024 | 55 | Moderate | PM2.5 |
| Nov 14, 2024 | 51 | Moderate | PM2.5 |
| Nov 13, 2024 | 31 | Good | Ozone |
| Nov 12, 2024 | 52 | Moderate | PM2.5 |
| Nov 11, 2024 | 47 | Good | PM2.5 |
| Nov 10, 2024 | 54 | Moderate | PM2.5 |
| Nov 9, 2024 | 33 | Good | Ozone |
| Nov 8, 2024 | 43 | Good | PM2.5 |
| Nov 7, 2024 | 39 | Good | PM2.5 |
| Nov 6, 2024 | 33 | Good | Ozone |
| Nov 5, 2024 | 38 | Good | Ozone |
| Nov 4, 2024 | 32 | Good | Ozone |
| Nov 3, 2024 | 42 | Good | Ozone |
| Nov 2, 2024 | 47 | Good | PM2.5 |
| Nov 1, 2024 | 42 | Good | PM2.5 |
| Oct 31, 2024 | 54 | Moderate | PM2.5 |
| Oct 30, 2024 | 28 | Good | PM2.5 |
| Oct 29, 2024 | 32 | Good | PM2.5 |
| Oct 28, 2024 | 48 | Good | PM10 |
| Oct 27, 2024 | 41 | Good | PM2.5 |
| Oct 26, 2024 | 52 | Moderate | PM2.5 |
| Oct 25, 2024 | 43 | Good | PM2.5 |
| Oct 24, 2024 | 45 | Good | Ozone |
| Oct 23, 2024 | 43 | Good | PM2.5 |
| Oct 22, 2024 | 38 | Good | Ozone |
| Oct 21, 2024 | 38 | Good | Ozone |
| Oct 20, 2024 | 50 | Good | PM2.5 |
| Oct 19, 2024 | 59 | Moderate | PM2.5 |
| Oct 18, 2024 | 33 | Good | PM2.5 |
| Oct 17, 2024 | 35 | Good | Ozone |
| Oct 16, 2024 | 53 | Moderate | PM10 |
| Oct 15, 2024 | 55 | Moderate | PM10 |
| Oct 14, 2024 | 50 | Good | PM2.5 |
| Oct 13, 2024 | 55 | Moderate | PM2.5 |
| Oct 12, 2024 | 59 | Moderate | PM2.5 |
| Oct 11, 2024 | 64 | Moderate | PM2.5 |
| Oct 10, 2024 | 63 | Moderate | PM2.5 |
| Oct 9, 2024 | 66 | Moderate | PM2.5 |
| Oct 8, 2024 | 67 | Moderate | PM2.5 |
| Oct 7, 2024 | 71 | Moderate | PM2.5 |
| Oct 6, 2024 | 71 | Moderate | PM2.5 |
| Oct 5, 2024 | 52 | Moderate | PM2.5 |
| Oct 4, 2024 | 58 | Moderate | PM10 |
| Oct 3, 2024 | 53 | Moderate | PM10 |
Monitoring Stations
ALONG SOUTH BOULDER CREEK NEXT TO LAFAYETTE WATER TREATMENT PLANT
BOULDER - CU-ATHENS
BOULDER CHAMBER OF COMMERCE
Boulder Fire Station
Boulder Reservoir
LONGMONT - MUNICIPAL BLDG
Longmont
Lyons
Niwot Ridge
Frequently Asked Questions
What is the air quality in Boulder, Colorado?
Based on EPA data from 2024, Boulder has a median Air Quality Index (AQI) of 49, which is classified as "Good." The primary pollutant is Ozone. Over the past 10 years, air quality has been stable.
Is Boulder a good place to live for air quality?
Boulder has a 10-year average median AQI of 47. In 2024, there were 212 days with "Good" air quality and 10 days with unhealthy conditions. No special precautions are needed for most people.
What pollutants affect Boulder the most?
The primary pollutant driving the AQI in Boulder is Ozone. This is monitored by 9 active EPA stations in the county. Other pollutants tracked include ozone, PM10, nitrogen dioxide, sulfur dioxide, and carbon monoxide.
How many air quality monitoring stations are in Boulder?
There are 9 active EPA monitoring stations in Boulder, Colorado. These stations continuously measure pollutant levels and contribute to the daily AQI calculations.