Air Quality Rankings for Hawaii 2026
Hawaii has 4 cities with EPA air quality data. Kauai, Hawaii has the cleanest air with a 5-year average AQI of 15. Honolulu, Hawaii has the highest AQI at 29.
| # | City | 5yr Avg AQI | Current AQI | Worst Pollutant | Trend | Grade |
|---|---|---|---|---|---|---|
| 1 | Kauai, Hawaii | 15 | 13 | PM2.5 | Improving | A |
| 2 | Maui, Hawaii | 21 | 20 | PM2.5 | Improving | A |
| 3 | Hawaii, Hawaii | 25 | 23 | PM2.5 | Improving | A |
| 4 | Honolulu, Hawaii | 29 | 31 | Ozone | Improving | B |
Air quality data for Hawaii is sourced from the EPA Air Quality System (AQS), which monitors outdoor air quality at thousands of stations nationwide.
Frequently Asked Questions
Kauai, Hawaii has the best air quality in Hawaii with a 5-year average AQI of 15 and a grade of A.
Hawaii has 4 cities with EPA air quality monitoring data in our database, covering multiple years of AQI measurements.
The Air Quality Index (AQI) measures five major pollutants: ground-level ozone, particulate matter (PM2.5 and PM10), carbon monoxide, sulfur dioxide, and nitrogen dioxide. Lower AQI values indicate cleaner air — 0-50 is "Good," while 150+ is "Unhealthy."
Cities ranked by 5-year average AQI (lower is better). Grades factor in average AQI, trend direction, unhealthy days, and dominant pollutant.