Santiago, Region Metropolitana, Chile Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
October Air Quality Analysis
Santiago, Region Metropolitana, Chile
AQI Trends: Highest and Lowest
Same Day Analysis (4th October ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 3rd highest AQI at 55 of Moderate air quality, showing improvement over 2024 and 2021 on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 4th Oct - 5th Oct 2025
Santiago, Region Metropolitana, Chile
7 AM4th Oct 2025
7 PM
6 AM5th Oct 2025
56AQI
47AQI
52AQI
45AQI
In the last 24 hours,
Santiago's AQI reached its highest point of 56 at 2 PM during the Day, while the lowest point, 45, was recorded at 4 AM during the Night between 4th Oct and 5th Oct 2025.
Day & Night AQI Trend : Sep - Oct 2025
Santiago, Region Metropolitana, Chile
12°C5/21°C
12°C5/18°C
10°C8/12°C
12°C6/17°C
13°C6/22°C
13°C7/21°C
16°C8/25°C
16°C10/24°C
14°C10/19°C
15°C10/21°C
15°C7/25°C
17°C9/25°C
15°C10/21°C
15°C9/23°C
14°C8/22°C
11°C8/17°C
10°C8/15°C
12°C3/21°C
15°C7/24°C
18°C10/28°C
17°C11/25°C
10°C5/16°C
12°C3/21°C
15°C7/23°C
16°C12/22°C
16°C9/24°C
18°C10/27°C
19°C12/29°C
18°C11/25°C
13°C11/17°C
--°C/°C
66AQI
55AQI
63AQI
56AQI
2025 Days Vs Air Quality
Santiago, Region Metropolitana, Chile
23%
64
53%
148
23%
63
0.7%
2
Total number of days with different AQI categories in last 278 days in 2025 (87 days remaining)
Under WHO’s Safe Air Quality Limits: 23%
Health Risk Level:
Very high
In 2025, 23% of 278 days were within WHO’s safe air quality limits. The risk of health issues is Very high, including respiratory issues, heart disease, and stress, particularly affecting vulnerable groups.
Annual Air Quality Insights
Santiago, Region Metropolitana, Chile
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
50AQI
45AQI
53AQI
51AQI
51AQI
49AQI
44AQI
45AQI
45AQI
51AQI
50AQI
46AQI
45AQI
51AQI
42AQI
35AQI
40AQI
39AQI
39AQI
47AQI
52AQI
41AQI
38AQI
46AQI
52AQI
64AQI
49AQI
47AQI
55AQI
55AQI
50AQI
46AQI
44AQI
39AQI
45AQI
42AQI
45AQI
51AQI
55AQI
64AQI
50AQI
56AQI
58AQI
63AQI
56AQI
47AQI
41AQI
48AQI
52AQI
52AQI
50AQI
50AQI
48AQI
43AQI
42AQI
43AQI
46AQI
56AQI
43AQI
36AQI
31AQI
34AQI
41AQI
46AQI
40AQI
36AQI
35AQI
46AQI
50AQI
52AQI
56AQI
56AQI
55AQI
50AQI
46AQI
54AQI
59AQI
55AQI
51AQI
54AQI
48AQI
53AQI
57AQI
51AQI
58AQI
55AQI
60AQI
68AQI
36AQI
55AQI
66AQI
66AQI
61AQI
63AQI
59AQI
53AQI
58AQI
73AQI
74AQI
67AQI
51AQI
71AQI
81AQI
54AQI
56AQI
59AQI
66AQI
77AQI
77AQI
72AQI
74AQI
72AQI
71AQI
57AQI
51AQI
59AQI
73AQI
72AQI
72AQI
87AQI
102AQI
96AQI
103AQI
80AQI
83AQI
109AQI
112AQI
59AQI
65AQI
97AQI
101AQI
102AQI
119AQI
104AQI
120AQI
120AQI
98AQI
101AQI
67AQI
83AQI
86AQI
113AQI
126AQI
115AQI
98AQI
53AQI
46AQI
87AQI
102AQI
89AQI
111AQI
125AQI
125AQI
144AQI
141AQI
149AQI
131AQI
140AQI
149AQI
130AQI
118AQI
108AQI
82AQI
84AQI
105AQI
91AQI
40AQI
85AQI
100AQI
115AQI
132AQI
108AQI
94AQI
70AQI
108AQI
96AQI
109AQI
128AQI
123AQI
148AQI
129AQI
148AQI
138AQI
137AQI
126AQI
128AQI
80AQI
88AQI
101AQI
100AQI
122AQI
142AQI
153AQI
158AQI
114AQI
150AQI
138AQI
129AQI
113AQI
129AQI
138AQI
132AQI
123AQI
131AQI
117AQI
111AQI
136AQI
150AQI
136AQI
112AQI
96AQI
59AQI
36AQI
43AQI
81AQI
94AQI
81AQI
84AQI
87AQI
121AQI
96AQI
117AQI
97AQI
88AQI
94AQI
95AQI
58AQI
65AQI
73AQI
70AQI
63AQI
56AQI
34AQI
32AQI
65AQI
80AQI
67AQI
78AQI
86AQI
82AQI
65AQI
57AQI
75AQI
75AQI
57AQI
59AQI
89AQI
83AQI
88AQI
75AQI
60AQI
59AQI
51AQI
64AQI
82AQI
54AQI
55AQI
61AQI
66AQI
71AQI
81AQI
68AQI
42AQI
21AQI
43AQI
60AQI
67AQI
58AQI
43AQI
53AQI
62AQI
47AQI
57AQI
66AQI
71AQI
77AQI
55AQI
47AQI
49AQI
49AQI
66AQI
95AQI
114AQI
124AQI
75AQI
62AQI
67AQI
No. of days
202576AQI
Highest AQI recorded in
July124AQI
Lowest AQI recorded in
January47AQI
202459AQI
Highest AQI recorded in
July98AQI
Lowest AQI recorded in
November38AQI
202364AQI
Highest AQI recorded in
July103AQI
Lowest AQI recorded in
November30AQI
202273AQI
Highest AQI recorded in
May125AQI
Lowest AQI recorded in
November45AQI
202178AQI
Highest AQI recorded in
July143AQI
Lowest AQI recorded in
November51AQI
202077AQI
Highest AQI recorded in
July110AQI
Lowest AQI recorded in
December52AQI
Most & Least Polluted Years Over the Last 6 Years
Santiago's annual 2025 AQI (76) shows an average percentage change of 9.2% (worsened AQI) compared to previous years: 2020 (77), 2021 (78), 2022 (73), 2023 (64), 2024 (59).