Metro area air quality · 2025

Bloomington, IN

Median AQI 42 (Good). 70.1% of monitored days rated Good across this metro's EPA monitoring network.

42
Median AQI
70.1%
Good-air days
0
Unhealthy days
44%
Cleaner than US metros

Aggregated from EPA Air Quality System (2025), 304 monitored days. EPA AQS →

The verdict

The Bloomington, IN metro runs good on the EPA scale, more polluted than the median US metro, a median AQI of 42 with 70.1% of 304 monitored days in the Good band.

42
median AQI · Good
70.1%
days rated Good
44%
cleaner than US metros
90
worst single reading

No day crossed into the Unhealthy tier across the metro's monitors in 2025.

Insights: Bloomington, IN metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 42 over 304 measured days in 2025, which corresponds to a Good band and a Moderate metro-wide health grade. The monitored-day split lands at 213 Good days (70%), 91 Moderate (30%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 61 while the highest single-day reading hit 90 (Moderate). Metro residents averaged roughly 21.0 clean-air days per 30-day window across the reporting year.

Across the 2020–2025 trend window, good days shifted by -26 and the median AQI moved -2 points, which classifies the multi-year trajectory as improving. The metro avoided any Unhealthy-tier days entirely, an outcome that typically reflects favorable wind patterns, lower industrial density, or effective regional emission controls. Metros with comparable AQI profiles include Albany-Schenectady-Troy, NY (66.3% good, AQI 42); Bismarck, ND (75.8% good, AQI 42); Cape Coral-Fort Myers, FL (74.4% good, AQI 42).

Air Quality Summary

Median AQI

42

Good

Good Days

70.1%

213 of 304 days

Max AQI

90

Moderate

Health Grade

Moderate

90th pct: 61

AQI Day Breakdown (2025)

Distribution of 304 monitored days across EPA AQI categories.

Good

213

70%

Moderate

91

30%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The Bloomington, IN metro area's air quality is rated Moderate based on 70.1% 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 Bloomington, IN metro compare?

How Bloomington, IN compares

Good-day share worse than US avg
Bloomington, IN 70.1%
Albany-Schenectady-Troy, NY 66.3%
US average 71.3%
Median AQI worse than US avg
Bloomington, IN 42
Albany-Schenectady-Troy, NY 42
US average 41
Unhealthy days / yr better than US avg
Bloomington, IN 0
Albany-Schenectady-Troy, NY 0
US average 1

5-Year Air Quality Trend

Air quality is improving in the Bloomington, IN metro. Best year: 2022 (261 good days).

Year Good Moderate Unhealthy Median AQI
2020 239 127 0 44
2021 220 145 0 44
2022 261 102 0 43
2023 213 140 1 47
2024 260 106 0 43
2025 213 91 0 42

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to Bloomington, IN.

Albany-Schenectady-Troy, NY

AQI 42 · 66.3% good

42

Bismarck, ND

AQI 42 · 75.8% good

42

Cape Coral-Fort Myers, FL

AQI 42 · 74.4% good

42

Daphne-Fairhope-Foley, AL

AQI 42 · 72.2% good

42

Decatur, AL

AQI 42 · 81.1% good

42

Deltona-Daytona Beach-Ormond Beach, FL

AQI 42 · 78.4% good

42

More Air Quality Data

Explore EPA air quality rankings and guides across U.S. metros and counties.

Cleanest Metro Areas

U.S. metros ranked by their share of Good air-quality days.

Worst Air Quality

Counties and metros with the most unhealthy air days.

All Metro Areas

Annual AQI by CBSA for every monitored U.S. metro area.

Best and Worst City Air

What drives urban air quality and how metro areas compare.

Air Quality Guides

Frequently Asked Questions

What is the air quality in the Bloomington, IN metro area? ▼
The Bloomington, IN metro area has a median Air Quality Index (AQI) of 42, rated "Good." 70.1% of monitored days (213 out of 304) had good air quality in 2025.
How many unhealthy air days does Bloomington, IN have? ▼
In 2025, the Bloomington, IN metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 90.
Is air quality in Bloomington, IN getting better or worse? ▼
Air quality in the Bloomington, IN metro is improving based on 5-year trends (2020-2025). Best year: 2022 with 261 good days. Worst year: 2025 with 213 good days.
What does AQI 42 mean for health? ▼
An AQI of 42 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
What is the 90th percentile AQI for Bloomington, IN? ▼
The 90th percentile AQI for the Bloomington, IN metro area is 61, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 90 (Moderate).
How does Bloomington, IN compare to other metro areas? ▼
The Bloomington, IN metro has 70.1% good air days. Similar metros: Albany-Schenectady-Troy, NY (66.3% good), Bismarck, ND (75.8% good), Cape Coral-Fort Myers, FL (74.4% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2025. 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 files (metro-level) · 2020–2025

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.