Peoria, Illinois Air Quality

Peoria air quality today — the AQI, the main pollutant, and whether it’s safe to exercise outside right now

Peoria, IL · Air quality right now

The air quality index in Peoria, IL is 25 (Good) right now — safe for outdoor activity.

Is it safe to be outside in Peoria today?

AQI 25 Yes — air quality is Good

Air is clean — great for outdoor activity.Main pollutant: OzoneObserved 10:00 AM CDT

Pollutants right now

ExerciseOK to run — no air-quality limits on outdoor exercise.

How to read Peoria’s air quality

Guides: The AQI Scale, Explained · Air Quality Alerts, Decoded · How to Read a Wildfire Smoke Map · Why Wildfire Smoke Travels 1,000 Miles.

Air quality over time in Peoria

Across the EPA’s county records from 2020 to 2025, Peoria’s cleanest year was 2020 (median AQI 44) and its most polluted was 2021 (median AQI 50); the typical (median) day has held roughly steady since 2020.

Peoria’s county air-quality record by year — the median and days in each AQI category, from the EPA’s Annual AQI by County summaries.
YearMedian AQIUnhealthy+Main pollutantUSGModerateGood
2020440PM2.51116247
2021500PM2.51179181
2022480PM2.50138181
2023481Ozone21131187
2024440PM2.50108236
2025452PM2.52139214

“USG” is Unhealthy for Sensitive Groups (AQI 101–150); “Unhealthy+” combines the Unhealthy, Very Unhealthy, and Hazardous days. In 2024 the EPA tightened the annual fine-particle (PM2.5) standard to 9 µg/m³ from the previous 12 µg/m³, so counties near the old limit read worse against the new one. Source: EPA AQS annual summaries, 20202025.

Frequently asked

What was the worst year for air quality in Peoria?
In the EPA's 2020–2025 county records, 2023 had the most days above AQI 100: 22 days (21 Unhealthy for Sensitive Groups, 1 Unhealthy or worse). The highest median AQI came in 2021 (50; 2023's was 48).
How many unhealthy air days does Peoria have?
Across 2020–2025, 1% of the days reported for Peoria's county had an AQI above 100 (28 of 2085), about 5 days a year. 2025 had 4 days.
What's the main air pollutant in Peoria?
PM2.5 drove Peoria's county AQI on the most days in 5 of 6 years (2020–2025); Ozone in 2023.