Masago, Narashino, Chiba, 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
Masago, Narashino, Chiba, Japan
AQI Trends: Highest and Lowest
Same Day Analysis (13th August ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 3rd highest AQI at 38 of Good air quality, showing improvement over 2024 and 2023 on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 13th Aug - 14th Aug 2025
Masago, Narashino, Chiba, Japan
4 AM13th Aug 2025
6 PM
3 AM14th Aug 2025
AQI
AQI
40AQI
27AQI
In the last 24 hours,
Masago's AQI reached its highest point of 40 at 3 PM during the Night, while the lowest point, 27, was recorded at 10 AM during the Night between 13th Aug and 14th Aug 2025.
Day & Night AQI Trend : Jul - Aug 2025
Masago, Narashino, Chiba, Japan
26°C25/28°C
26°C25/27°C
27°C25/30°C
27°C25/31°C
27°C25/30°C
28°C25/31°C
29°C26/32°C
29°C26/33°C
29°C26/33°C
29°C25/34°C
29°C26/33°C
29°C26/33°C
29°C26/33°C
29°C26/34°C
29°C25/35°C
29°C25/33°C
27°C24/32°C
27°C25/30°C
29°C25/34°C
30°C26/34°C
30°C27/33°C
30°C27/34°C
31°C28/35°C
30°C28/34°C
28°C24/33°C
28°C24/32°C
27°C25/27°C
27°C26/28°C
28°C26/29°C
--°C/°C
--°C/°C
41AQI
35AQI
42AQI
36AQI
2025 Days Vs Air Quality
Masago, Narashino, Chiba, Japan
89%
201
11%
24
Total number of days with different AQI categories in last 225 days in 2025 (140 days remaining)
Under WHO’s Safe Air Quality Limits: 89%
Health Risk Level:
Low
In 2025, 89% of 225 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
Masago, Narashino, Chiba, Japan
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
32AQI
32AQI
25AQI
29AQI
37AQI
53AQI
32AQI
35AQI
29AQI
29AQI
28AQI
35AQI
29AQI
48AQI
46AQI
43AQI
36AQI
34AQI
57AQI
41AQI
43AQI
39AQI
55AQI
48AQI
42AQI
38AQI
36AQI
40AQI
31AQI
32AQI
29AQI
35AQI
32AQI
39AQI
32AQI
32AQI
30AQI
29AQI
30AQI
29AQI
29AQI
31AQI
32AQI
33AQI
29AQI
30AQI
37AQI
35AQI
32AQI
30AQI
29AQI
30AQI
31AQI
32AQI
33AQI
33AQI
36AQI
39AQI
56AQI
50AQI
62AQI
42AQI
39AQI
26AQI
32AQI
31AQI
32AQI
33AQI
34AQI
40AQI
44AQI
44AQI
41AQI
34AQI
25AQI
20AQI
23AQI
17AQI
22AQI
44AQI
50AQI
58AQI
53AQI
66AQI
79AQI
71AQI
49AQI
39AQI
40AQI
32AQI
28AQI
22AQI
21AQI
21AQI
23AQI
26AQI
29AQI
39AQI
27AQI
46AQI
42AQI
37AQI
28AQI
39AQI
31AQI
32AQI
47AQI
52AQI
61AQI
50AQI
43AQI
43AQI
30AQI
37AQI
35AQI
44AQI
49AQI
43AQI
35AQI
45AQI
40AQI
28AQI
31AQI
39AQI
36AQI
29AQI
25AQI
26AQI
29AQI
23AQI
30AQI
28AQI
36AQI
36AQI
42AQI
43AQI
31AQI
46AQI
42AQI
62AQI
42AQI
39AQI
39AQI
36AQI
31AQI
27AQI
24AQI
23AQI
26AQI
25AQI
16AQI
21AQI
28AQI
33AQI
30AQI
40AQI
45AQI
49AQI
54AQI
41AQI
31AQI
25AQI
31AQI
32AQI
32AQI
36AQI
43AQI
50AQI
47AQI
43AQI
37AQI
33AQI
22AQI
23AQI
22AQI
21AQI
22AQI
27AQI
27AQI
31AQI
34AQI
35AQI
37AQI
37AQI
40AQI
46AQI
59AQI
66AQI
72AQI
69AQI
56AQI
52AQI
54AQI
52AQI
45AQI
44AQI
43AQI
44AQI
41AQI
35AQI
34AQI
35AQI
31AQI
34AQI
34AQI
30AQI
31AQI
29AQI
34AQI
29AQI
30AQI
29AQI
33AQI
40AQI
43AQI
61AQI
50AQI
51AQI
50AQI
48AQI
50AQI
40AQI
38AQI
36AQI
38AQI
38AQI
33AQI
41AQI
37AQI
33AQI
34AQI
42AQI
44AQI
No. of days
202537AQI
Highest AQI recorded in
August44AQI
Lowest AQI recorded in
February33AQI
202439AQI
Highest AQI recorded in
July53AQI
Lowest AQI recorded in
September30AQI
202344AQI
Highest AQI recorded in
July49AQI
Lowest AQI recorded in
December40AQI
202244AQI
Highest AQI recorded in
June49AQI
Lowest AQI recorded in
August36AQI
202138AQI
Highest AQI recorded in
December45AQI
Lowest AQI recorded in
March30AQI
202037AQI
Highest AQI recorded in
August48AQI
Lowest AQI recorded in
September30AQI
Most & Least Polluted Years Over the Last 6 Years
Masago's annual 2025 AQI (37) shows an average percentage change of -7.4% (improved AQI) compared to previous years: 2020 (37), 2021 (38), 2022 (44), 2023 (44), 2024 (39).