# Counties in Wyoming by highest daily Air Quality Index (US EPA), 2024

All 19 values come from U.S. Environmental Protection Agency for 2024, so the places are comparable. 2 counties have no value for that period and are not ranked.

- Indicator id: `aqi_max`
- Unit: index
- Definition: Highest daily Air Quality Index (AQI) value recorded in a US county during the year, from the EPA AirData annual summaries. Values above 500 are beyond the AQI scale and are published as EPA computes them.
- Source: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: highest daily AQI (https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual)
- Publisher page: https://invokely.ai/en/publishers/environmental-protection-agency
- Retrieved: 2026-10-12
- Citation: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
- Web page: https://invokely.ai/rankings/highest-daily-air-quality-index/wyoming-counties

| Rank | Place | index |
|---:|---|---:|
| 1 | Platte County | 927 |
| 2 | Sheridan County | 205 |
| 3 | Albany County | 187 |
| 4 | Campbell County | 161 |
| 5 | Laramie County | 151 |
| 6 | Fremont County | 139 |
| 7 | Teton County | 138 |
| 8 | Sweetwater County | 137 |
| 9 | Natrona County | 136 |
| 9 | Weston County | 136 |
| 11 | Converse County | 126 |
| 12 | Big Horn County | 119 |
| 13 | Sublette County | 115 |
| 14 | Johnson County | 112 |
| 15 | Park County | 88 |
| 16 | Washakie County | 83 |
| 17 | Lincoln County | 77 |
| 18 | Uinta County | 44 |
| 19 | Carbon County | 35 |