Metro area air quality · 2025
Champaign-Urbana, IL
Median AQI 43 (Good). 65.8% of monitored days rated Good across this metro's EPA monitoring network.
- 43
- Median AQI
- 65.8%
- Good-air days
- 0
- Unhealthy days
- 35%
- Cleaner than US metros
Champaign-Urbana, IL posted a 2025 median AQI of 43 (Good) with 65.8% Good days
According to the U.S. EPA Air Quality System, the Champaign-Urbana, IL CBSA recorded a median AQI of 43 across 365 monitored days in 2025, with 65.8% rated Good and 0 unhealthy or worse. This is an annual metro comparison, not a live advisory.
Data source EPA Air Quality System (AQS)
- Cleaner than US metros
- The Champaign-Urbana, IL CBSA's 65.8% Good-day share places it cleaner than 35% of US metros in 2025.
- Closest median-AQI peer
- Ashtabula, OH (81.2% Good, median AQI 43) is the closest nationwide median-AQI peer to Champaign-Urbana, IL.
- 2020–2025 Good-day shift
- Champaign-Urbana, IL's Good-day share moved -2.2 points from 2020 to 2025 (median AQI -1).
- Median AQI
- Median AQI: 43
Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →
The verdict
Champaign-Urbana, IL's peak reading 138 is in the upper max-AQI tercile among CBSA metros here. On the EPA scale the metro runs good, more polluted than the median US metro, with a median AQI of 43 and 65.8% of 365 monitored days in the Good band.
- 43
- median AQI · Good
- 65.8%
- days rated Good
- 35%
- cleaner than US metros
- 138
- worst single reading
No day crossed into the Unhealthy tier across the metro's monitors in 2025.
Annual release change
What changed in the 2025 EPA annual release
- Champaign-Urbana, IL metro's peak single-day AQI rose from 100 to 138 between the 2024 and 2025 EPA annual releases, a change of +38 points.
- Champaign-Urbana, IL metro's Good-day share fell from 68.3% to 66.5% between the 2024 and 2025 EPA annual releases, a change of -1.8 percentage points.
Champaign-Urbana, IL's peak reading 138 is in the upper max-AQI tercile among CBSA metros here. Signature read: peak AQI 138 (high tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 43 over 365 measured days in 2025 (Good / Moderate). The monitored-day split lands at 240 Good (66%), 121 Moderate (33%), and 4 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 66; the highest single-day reading hit 138 (USG).
Across 2020–2025, Good-day share shifted -2.2 points and median AQI moved -1 (stable). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Ashtabula, OH (81.2% good, AQI 43); Bloomington, IN (67.7% good, AQI 43); Cleveland, MS (71.9% good, AQI 43).
Air Quality Summary
Median AQI
43
Good
Good Days
65.8%
240 of 365 days
Max AQI
138
USG
Health Grade
Moderate
90th pct: 66
AQI Day Breakdown (2025)
Distribution of 365 monitored days across EPA AQI categories.
Good
240
66%
Moderate
121
33%
USG
4
1%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Health Impact Assessment
The Champaign-Urbana, IL metro area's air quality is rated Moderate based on 65.8% good air days. No unhealthy air days were recorded in 2025.
Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.
How does the Champaign-Urbana, IL metro compare?
How Champaign-Urbana, IL compares
5-Year Air Quality Trend
Air quality is stable in the Champaign-Urbana, IL metro. Highest Good-day share: 2020 (68.7%, 250 of 364 monitored days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 250 | 114 | 0 | 44 | 126 |
| 2021 | 236 | 129 | 0 | 44 | 99 |
| 2022 | 223 | 141 | 0 | 44 | 126 |
| 2023 | 196 | 156 | 1 | 48 | 277 |
| 2024 | 250 | 116 | 0 | 44 | 100 |
| 2025 | 240 | 121 | 0 | 43 | 138 |
Metros with a similar median AQI
CBSA peers nationwide whose annual median AQI sits near Champaign-Urbana, IL (43).
Ashtabula, OH
Median AQI 43 · 81.2% Good-day share
Bloomington, IN
Median AQI 43 · 67.7% Good-day share
Cleveland, MS
Median AQI 43 · 71.9% Good-day share
Columbus, IN
Median AQI 43 · 72.6% Good-day share
Durham-Chapel Hill, NC
Median AQI 43 · 71.5% Good-day share
Elizabethtown-Fort Knox, KY
Median AQI 43 · 73.4% Good-day share
Metros with similar unhealthy-day exposure
A second relationship type: metros whose unhealthy-or-worse day count is closest to Champaign-Urbana, IL's 0 (independent of median AQI).
Aberdeen, SD
0 unhealthy-or-worse days · median AQI 27
Aberdeen, WA
0 unhealthy-or-worse days · median AQI 22
Adrian, MI
0 unhealthy-or-worse days · median AQI 41
Akron, OH
0 unhealthy-or-worse days · median AQI 45
Albany, GA
0 unhealthy-or-worse days · median AQI 46
Albany, OR
0 unhealthy-or-worse days · median AQI 27
Frequently Asked Questions
What is the 90th percentile AQI for Champaign-Urbana, IL? ▼
How many unhealthy air days does Champaign-Urbana, IL have? ▼
What is the air quality in the Champaign-Urbana, IL metro area? ▼
Is air quality in Champaign-Urbana, IL getting better or worse? ▼
What does AQI 43 mean for health? ▼
How does Champaign-Urbana, IL compare to other metro areas? ▼
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Champaign-Urbana, IL, 2025. See our methodology for how AQI, median, and coverage figures are computed.
Read our methodology , how this data is sourced, computed, and verified.
Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary, Champaign-Urbana, IL · 2020–2025