Illinois · County air quality · 2025

Kane County, Illinois

Median AQI 46 (Good). 60.8% of monitored days rated Good, direct from EPA Air Quality System stations.

46
Median AQI
60.8%
Good-air days
1
Unhealthy days
16%
Cleaner than US counties

The verdict

According to EPA Air Quality System monitoring data, Kane County's air is good on balance, among the more polluted 10% of US counties, a median AQI of 46 with 60.8% of 273 monitored days in the Good band, driven mainly by PM2.5.

46
median AQI · Good
60.8%
days rated Good
PM2.5
main pollutant
16%
cleaner than US counties

1 day reached Unhealthy or worse; the worst single reading hit AQI 165.

Data updated July 2026

Kane County AQI category distribution Stacked-segment bar showing the share of monitored days that fell in each EPA AQI category, Good, Moderate, USG, Unhealthy, Very Unhealthy, Hazardous, with median AQI marker. AQI category distribution 273 monitored days G M Median AQI 46 0 50 100 150 200 300 500 Kane County
  • Good · 166 d · 60.8%
  • Moderate · 98 d · 35.9%
  • USG · 8 d · 2.9%
  • Unhealthy · 1 d · 0.4%

How did Kane County's air break down in 2025?

Across 273 monitored days, 166 fell in the Good band (AQI 0–50) and 1 reached Unhealthy or worse. The worst single day peaked at AQI 165 (Unhealthy).

EPA AQS →

Air quality data from EPA Air Quality System (2025). 273 days monitored. Median AQI: 46 (Good).

Insights: Kane County, Illinois. EPA monitors recorded a median Air Quality Index of 46 across 273 measured days in 2025, earning a Good classification and a Moderate health grade. Of those days, 166 (61%) fell in the Good band (AQI 0–50), 98 (36%) registered Moderate readings, and 8 (3%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 83, while the worst single-day peak hit 165 (Unhealthy). Residents averaged about 18.2 clean-air days per 30-day window during the monitoring year.

The full pollutant mix ranks as PM2.5 (142 days), Ozone (131 days). Across the 2020–2025 trend window, good days shifted by -38 and the median AQI moved +4 points, placing the multi-year trajectory at worsening. Residents and visitors experienced 1 unhealthy-or-worse days combined, periods when the EPA recommends sensitive groups limit prolonged outdoor exertion. Nearby counties show comparable readings: Adams (94.4% good, AQI 38); Champaign (63.7% good, AQI 44); Clark (92.1% good, AQI 36); Cook (40.5% good, AQI 53); DuPage (61.2% good, AQI 44); Effingham (95.7% good, AQI 35).

Air Quality Summary

Median AQI

46

Good

Good Days

60.8%

166 of 273 monitored days

-14.2pp vs 75% target

Max AQI Recorded

165

Unhealthy

Health Grade

Moderate

90th-pct AQI 83

Kane County, Good days share 60.8%
National avg

Share of monitored days at AQI 0-50 (Good band).

Kane County, Unhealthy-or-worse share 0.4%
National avg

Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).

AQI Day Breakdown (2025)

Distribution of 273 monitored days across EPA AQI categories.

Good

166

61%

Moderate

98

36%

USG

8

3%

Unhealthy

1

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Pollutant Breakdown

Days where each pollutant was the primary driver of AQI readings in Kane County.

Kane County, Illinois criteria pollutant distribution Stratified-band visualization showing the share of monitored days each criteria pollutant (PM2.5, PM10, O3, NO2, CO) was the primary AQI driver. PM2.5 · 52.0% Ozone · 48.0% 0% 25% 50% 75% 100% Kane County, Illinois · 273 monitored days Criteria pollutant column
  • PM2.5 · 142 days · 52.0%
  • Ozone · 131 days · 48.0%
Fine Particles (PM2.5) 142 days (52%)

How PM2.5 affects health →

Ozone (O3) 131 days (48%)

How Ozone affects health →

Health Impact Assessment

Moderate

Kane County's air quality is rated Moderate based on 60.8% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.

Air quality is acceptable most days, but 8 days reached "Unhealthy for Sensitive Groups" (AQI 101-150) and peak AQI reached 165. Sensitive groups should monitor real-time conditions at AirNow.gov.

The dominant pollutant is PM2.5, driving AQI on 142 of 273 monitored days.

5-Year Air Quality Trend

Air quality is worsening in Kane County. Best year: 2024 (237 good days).

Year Good Moderate USG Unhealthy Median AQI
2020 204 68 6 1 42
2021 188 96 1 0 44
2022 189 93 3 0 42
2023 178 89 16 5 46
2024 237 90 1 0 42
2025 166 98 8 1 46

How does Kane County compare?

How Kane County compares

Good-day share worse than US avg
Kane County 60.8%
Adams County, Illinois 94.4%
US average 76.5%
Median AQI worse than US avg
Kane County 46
Adams County, Illinois 38
US average 38
Unhealthy days / yr worse than US avg
Kane County 1
Adams County, Illinois 0
US average 0

Other Counties in Illinois

Air quality comparison for nearby counties in Illinois.

Counties with Similar Air Quality

Counties across the US with a similar median AQI to Kane County.

What Kane County's air means for you

On most days the air here is fine, but PM2.5 drives 1 unhealthy-or-worse day a year that sensitive groups should plan around.

  • Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-PM2.5 days, the guide explains what a median of 46 means for exposure. Health guidance
  • See how Kane County ranks against every monitored U.S. county on Good-day share. County rankings
  • Compare Kane County with its Illinois neighbours before drawing a conclusion about the region. All of Illinois

Based on 273 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.

More Air Quality Data

Air Quality Guides

Frequently Asked Questions

What is the air quality in Kane County, Illinois?
Kane County has a median Air Quality Index (AQI) of 46, rated "Good." 60.8% of monitored days (166 out of 273) had good air quality in 2025.
What is the main pollutant in Kane County?
The primary pollutant in Kane County is Fine Particles (PM2.5), which was the main AQI driver on 142 days (52% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Kane County have?
In 2025, Kane County recorded 1 unhealthy air days (1 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 165.
Is the air quality in Kane County getting better or worse?
Air quality in Kane County is worsening based on 5-year trends (2020-2025). Best year: 2024 with 237 good days. Worst year: 2025 with 166 good days.
What does AQI 46 mean for health?
Kane County's median AQI of 46 falls in the "Good" category. See the <a href="/guides/understanding-aqi" class="underline">AQI category guide</a> for what each range means for health.
How does Kane County compare to other counties in Illinois?
Kane County has 60.8% good air days. Nearby counties in Illinois: Adams (94.4% good), Champaign (63.7% good), Clark (92.1% good), Cook (40.5% good), DuPage (61.2% good), Effingham (95.7% good).
What is the 90th percentile AQI in Kane County?
The 90th percentile AQI for Kane County is 83, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 165 (Unhealthy).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.

Informational only, not professional advice. Data from EPA AQS. See our disclaimer.

Every figure on PlainAir is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.