Koganei, Tokyo, Japan Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
September Air Quality Analysis
Koganei, Tokyo, Japan
AQI Trends: Highest and Lowest
Same Day Analysis (16th September ):
On this day, AQI across the 1 years varied significantly: 2025 ranks 1st highest AQI at 39 of Good air quality on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 17th Sep - 18th Sep 2025
Koganei, Tokyo, Japan
5 AM17th Sep 2025
6 PM
4 AM18th Sep 2025
AQI
AQI
60AQI
35AQI
In the last 24 hours,
Koganei's AQI reached its highest point of 60 at 2 PM during the Night, while the lowest point, 35, was recorded at 3 AM during the Night between 17th Sep and 18th Sep 2025.
Day & Night AQI Trend : Aug - Sep 2025
Koganei, Tokyo, Japan
31°C27/36°C
32°C29/36°C
32°C29/37°C
31°C28/35°C
32°C29/36°C
33°C30/37°C
32°C29/37°C
31°C29/34°C
32°C29/36°C
29°C27/32°C
30°C27/34°C
32°C29/37°C
33°C30/37°C
32°C29/35°C
32°C29/36°C
32°C29/36°C
27°C27/28°C
25°C23/26°C
27°C24/32°C
29°C26/32°C
31°C27/35°C
30°C28/33°C
30°C28/32°C
27°C24/30°C
25°C24/27°C
27°C24/31°C
29°C27/33°C
29°C26/32°C
29°C28/33°C
--°C/°C
--°C/°C
48AQI
42AQI
44AQI
39AQI
2025 Days Vs Air Quality
Koganei, Tokyo, Japan
86%
96
14%
15
Total number of days with different AQI categories in last 260 days in 2025 (105 days remaining)
Under WHO’s Safe Air Quality Limits: 86%
Health Risk Level:
Low
In 2025, 86% of 260 days were within WHO’s safe air quality limits. The risk of health issues is Low, but the long-term effects, especially on vulnerable individuals, remain uncertain.
Annual Air Quality Insights
Koganei, Tokyo, Japan
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
32AQI
19AQI
15AQI
19AQI
25AQI
21AQI
23AQI
34AQI
38AQI
41AQI
48AQI
35AQI
32AQI
27AQI
33AQI
32AQI
27AQI
25AQI
29AQI
38AQI
32AQI
33AQI
34AQI
27AQI
19AQI
19AQI
17AQI
16AQI
16AQI
22AQI
22AQI
26AQI
34AQI
38AQI
45AQI
41AQI
44AQI
47AQI
54AQI
69AQI
75AQI
78AQI
63AQI
55AQI
56AQI
55AQI
47AQI
47AQI
46AQI
46AQI
42AQI
38AQI
37AQI
38AQI
37AQI
40AQI
41AQI
38AQI
37AQI
34AQI
37AQI
39AQI
32AQI
34AQI
33AQI
40AQI
44AQI
58AQI
52AQI
50AQI
45AQI
46AQI
47AQI
40AQI
39AQI
35AQI
33AQI
35AQI
34AQI
36AQI
40AQI
42AQI
46AQI
46AQI
49AQI
50AQI
48AQI
56AQI
56AQI
55AQI
50AQI
47AQI
50AQI
54AQI
53AQI
45AQI
38AQI
37AQI
33AQI
30AQI
29AQI
30AQI
37AQI
41AQI
37AQI
31AQI
32AQI
28AQI
35AQI
39AQI
39AQI
22AQI
28AQI
46AQI
45AQI
35AQI
No. of days
202539AQI
Highest AQI recorded in
July46AQI
Lowest AQI recorded in
May22AQI
Most & Least Polluted Years Over the Last 1 Years
Koganei's annual 2025 AQI (39) shows an average percentage change of NaN% (improved AQI) compared to previous years: .