Koyo, Nagoya, Aichi, Japan Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
August Air Quality Analysis
Koyo, Nagoya, Aichi, Japan
AQI Trends: Highest and Lowest
Same Day Analysis (11th August ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 1st highest AQI at 41 of Good air quality on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 11th Aug - 12th Aug 2025
Koyo, Nagoya, Aichi, Japan
4 AM11th Aug 2025
7 PM
3 AM12th Aug 2025
AQI
AQI
46AQI
22AQI
In the last 24 hours,
Koyo's AQI reached its highest point of 46 at 4 AM during the Night, while the lowest point, 22, was recorded at 2 PM during the Night between 11th Aug and 12th Aug 2025.
Day & Night AQI Trend : Jul - Aug 2025
Koyo, Nagoya, Aichi, Japan
28°C26/31°C
28°C25/31°C
28°C26/31°C
27°C25/30°C
25°C24/26°C
26°C23/30°C
27°C24/30°C
28°C25/31°C
29°C26/32°C
29°C26/33°C
29°C26/33°C
29°C26/33°C
29°C27/32°C
29°C26/32°C
29°C26/32°C
29°C26/32°C
30°C27/35°C
30°C27/34°C
30°C27/33°C
31°C27/36°C
31°C27/35°C
31°C28/35°C
31°C28/35°C
31°C28/34°C
32°C28/36°C
29°C27/32°C
29°C25/33°C
29°C25/32°C
25°C24/25°C
--°C/°C
--°C/°C
42AQI
33AQI
43AQI
37AQI
2025 Days Vs Air Quality
Koyo, Nagoya, Aichi, Japan
91%
204
9%
19
Total number of days with different AQI categories in last 223 days in 2025 (142 days remaining)
Under WHO’s Safe Air Quality Limits: 91%
Health Risk Level:
Very Low
In 2025, 91% of 223 days were within WHO’s safe air quality limits. The risk of health issues is Very Low, but health impacts are still unclear.
Annual Air Quality Insights
Koyo, Nagoya, Aichi, Japan
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
26AQI
28AQI
28AQI
26AQI
25AQI
22AQI
25AQI
24AQI
25AQI
21AQI
23AQI
22AQI
25AQI
28AQI
29AQI
24AQI
26AQI
24AQI
26AQI
26AQI
31AQI
30AQI
34AQI
35AQI
35AQI
32AQI
25AQI
28AQI
29AQI
28AQI
31AQI
34AQI
26AQI
29AQI
28AQI
29AQI
28AQI
28AQI
28AQI
27AQI
28AQI
29AQI
22AQI
31AQI
28AQI
31AQI
30AQI
30AQI
29AQI
29AQI
28AQI
29AQI
30AQI
31AQI
32AQI
28AQI
34AQI
36AQI
34AQI
36AQI
35AQI
34AQI
23AQI
24AQI
31AQI
31AQI
28AQI
35AQI
31AQI
27AQI
24AQI
32AQI
20AQI
19AQI
17AQI
15AQI
15AQI
14AQI
18AQI
29AQI
33AQI
39AQI
41AQI
53AQI
78AQI
67AQI
42AQI
35AQI
33AQI
37AQI
24AQI
25AQI
17AQI
18AQI
20AQI
18AQI
21AQI
23AQI
19AQI
25AQI
25AQI
25AQI
20AQI
25AQI
18AQI
21AQI
26AQI
32AQI
31AQI
31AQI
24AQI
24AQI
15AQI
14AQI
27AQI
23AQI
26AQI
24AQI
25AQI
27AQI
24AQI
21AQI
19AQI
19AQI
18AQI
16AQI
15AQI
16AQI
16AQI
14AQI
15AQI
20AQI
23AQI
25AQI
24AQI
23AQI
20AQI
24AQI
25AQI
32AQI
31AQI
24AQI
23AQI
22AQI
17AQI
17AQI
17AQI
16AQI
20AQI
16AQI
17AQI
15AQI
19AQI
15AQI
19AQI
19AQI
21AQI
24AQI
29AQI
22AQI
22AQI
21AQI
23AQI
24AQI
21AQI
20AQI
23AQI
25AQI
26AQI
30AQI
30AQI
26AQI
21AQI
17AQI
16AQI
17AQI
17AQI
21AQI
20AQI
25AQI
48AQI
58AQI
83AQI
72AQI
71AQI
80AQI
65AQI
68AQI
76AQI
87AQI
63AQI
52AQI
51AQI
52AQI
42AQI
48AQI
47AQI
43AQI
37AQI
35AQI
34AQI
36AQI
34AQI
36AQI
35AQI
28AQI
26AQI
26AQI
30AQI
36AQI
38AQI
39AQI
44AQI
44AQI
46AQI
64AQI
52AQI
52AQI
46AQI
39AQI
48AQI
41AQI
41AQI
27AQI
30AQI
32AQI
23AQI
20AQI
23AQI
49AQI
47AQI
No. of days
202530AQI
Highest AQI recorded in
July49AQI
Lowest AQI recorded in
May20AQI
202433AQI
Highest AQI recorded in
April47AQI
Lowest AQI recorded in
December25AQI
202338AQI
Highest AQI recorded in
April46AQI
Lowest AQI recorded in
August25AQI
202233AQI
Highest AQI recorded in
March48AQI
Lowest AQI recorded in
July24AQI
202128AQI
Highest AQI recorded in
November40AQI
Lowest AQI recorded in
January13AQI
202016AQI
Highest AQI recorded in
August20AQI
Lowest AQI recorded in
December12AQI
Most & Least Polluted Years Over the Last 6 Years
Koyo's annual 2025 AQI (30) shows an average percentage change of 11.8% (worsened AQI) compared to previous years: 2020 (16), 2021 (28), 2022 (33), 2023 (38), 2024 (33).