Daily Air Quality Index summaries from EPA monitors in Kalamazoo, Michigan, 1991–2025.
61%
Good days in 2025
43
Median daily AQI, 2025
7
Days above 100 in 2025
365
Days with an AQI in 2025 (of 365)
In 2025, EPA reported a daily Air Quality Index (AQI) for Kalamazoo, Michigan on 365 days. 224 of those days (61%) were in the Good range, and the median daily AQI was 43. That median is higher than the typical monitored county in Michigan (median 39 across 26 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 251 days. Across the years with fuller monitoring, the share of Good days fell: an average of 85% in 1991–1993 versus 56% in 2023–2025.
How the days broke down each year
Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.
Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous
Typical and high-end AQI over time
The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.
Median daily AQI
90th-percentile daily AQI
Main pollutant by day, 2025
On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.
Pollutant
Days as main pollutant
Share of monitored days
Fine particles (PM2.5)
251
69%
Ozone
114
31%
Year-by-year data
Annual AQI summary by year
Year
Days with AQI
Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous
Median AQI
90th pct.
Max AQI
Main pollutant
2025
365
224
134
6
1
0
0
43
71
156
PM2.5
2024
366
234
132
0
0
0
0
45
63
100
PM2.5
2023
358
151
198
6
2
1
0
53
77
225
PM2.5
2022
352
177
172
3
0
0
0
50
69
134
PM2.5
2021
349
177
172
0
0
0
0
50
70
100
PM2.5
2020
323
239
78
6
0
0
0
41
61
115
PM2.5
2019
362
260
102
0
0
0
0
43
58
87
PM2.5
2018
356
217
135
4
0
0
0
44
65
115
PM2.5
2017
365
223
141
1
0
0
0
44
61
101
PM2.5
2016
363
221
134
8
0
0
0
44
64
119
PM2.5
2015
359
206
152
1
0
0
0
47
66
101
PM2.5
2014
363
175
186
2
0
0
0
51
66
108
PM2.5
2013
241
165
75
1
0
0
0
44
67
105
Ozone
2012
243
130
93
18
2
0
0
48
97
192
Ozone
2011
231
152
71
8
0
0
0
43
72
133
Ozone
2010
242
148
93
1
0
0
0
44
71
119
Ozone
2009
243
154
84
5
0
0
0
45
74
126
Ozone
2008
238
133
102
3
0
0
0
48
74
129
Ozone
2007
239
121
103
15
0
0
0
50
93
147
Ozone
2006
241
133
105
3
0
0
0
48
77
119
Ozone
2005
239
109
111
18
1
0
0
54
97
156
Ozone
2004
241
143
96
2
0
0
0
45
75
105
Ozone
2003
238
117
103
15
3
0
0
51
93
164
Ozone
2002
242
112
99
22
9
0
0
53
108
190
Ozone
2001
243
118
99
23
3
0
0
53
102
169
Ozone
2000
242
138
98
6
0
0
0
47
81
143
Ozone
1999
238
110
95
24
9
0
0
53
115
179
Ozone
1998
182
101
55
22
4
0
0
49
112
190
Ozone
1997
180
119
44
14
3
0
0
45
100
164
Ozone
1996
275
201
51
18
5
0
0
44
93
169
Ozone
1995
365
300
42
15
7
1
0
36
77
201
Ozone
1994
365
280
69
14
2
0
0
38
77
169
Ozone
1993
365
294
57
11
3
0
0
36
74
164
Ozone
1992
366
307
44
9
5
1
0
32
74
205
Ozone
1991
153
140
11
2
0
0
0
29
50
140
Ozone
What this data can and can’t tell you
It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.
It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.
Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.
Counties in Michigan with a similar median AQI in 2025
