Hoan Kiem District, Ha Noi, Vietnam Historical Air Quality Analysis

Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!

Good

050

Moderate

100

Poor

150

Unhealthy

200

Severe

300

Hazardous

301+

September Air Quality Analysis
Hoan Kiem District, Ha Noi, Vietnam

2023

2024

2025

AQI

Days

Days	2025	2024	2023
Sep. 1	43	35	116
Sep. 2	43	47	111
Sep. 3	42	39	93
Sep. 4	46		82
Sep. 5	42		93
Sep. 6	41		105
Sep. 7	50		118
Sep. 8	56		79
Sep. 9	52		92
Sep. 10	50		106
Sep. 11	45		105
Sep. 12	44		102
Sep. 13	41		68
Sep. 14	42		68
Sep. 15	46		73
Sep. 16	49		82
Sep. 17	51		87
Sep. 18			77
Sep. 19			56
Sep. 20			56
Sep. 21			55
Sep. 22			57
Sep. 23			61
Sep. 24			79
Sep. 25			96
Sep. 26			95
Sep. 27			71
Sep. 28			69
Sep. 29			104
Sep. 30			100

AQI Trends: Highest and Lowest

Highest AQI recorded on

7th Sep 2023

118AQI

Lowest AQI recorded on

1st Sep 2024

35AQI

Same Day Analysis (17th September ):
On this day, AQI across the 3 years varied significantly: 2025 ranks 2nd highest AQI at 51 of Moderate air quality, showing improvement over 2023 on the same day.

Day & Night AQI Trend: 17th Sep - 18th Sep 2025
Hoan Kiem District, Ha Noi, Vietnam

AQI

Day

Night

5 AM17th Sep 2025

6 PM

4 AM18th Sep 2025

Day time

Avg. Highest Time

8AM17th Sep

68AQI

Avg. Lowest Time

1PM17th Sep

34AQI

Night time

Avg. Highest Time

9PM17th Sep

58AQI

Avg. Lowest Time

6PM17th Sep

43AQI

In the last 24 hours,

Hoan Kiem District's AQI reached its highest point of 68 at 8 AM during the Day, while the lowest point, 34, was recorded at 1 PM during the Day between 17th Sep and 18th Sep 2025.

Day & Night AQI Trend : Aug - Sep 2025
Hoan Kiem District, Ha Noi, Vietnam

AugSep

19th - 20th20th - 21st21st - 22nd22nd - 23rd23rd - 24th24th - 25th25th - 26th26th - 27th27th - 28th28th - 29th29th - 30th30th - 31st31st - 01st01st - 02nd02nd - 03rd03rd - 04th04th - 05th05th - 06th06th - 07th07th - 08th08th - 09th09th - 10th10th - 11th11th - 12th12th - 13th13th - 14th14th - 15th15th - 16th16th - 17th17th - 18th18th

Day

Night

25°C24/26°C

28°C24/33°C

28°C25/31°C

27°C25/31°C

28°C25/33°C

29°C25/34°C

25°C24/29°C

24°C23/25°C

25°C24/28°C

27°C23/32°C

27°C24/32°C

27°C24/31°C

27°C24/30°C

27°C25/31°C

28°C25/33°C

28°C25/34°C

29°C25/34°C

29°C25/33°C

29°C26/35°C

30°C26/35°C

30°C26/36°C

28°C26/32°C

28°C25/31°C

28°C25/33°C

28°C25/32°C

28°C25/33°C

28°C25/31°C

28°C24/33°C

27°C25/31°C

5 AM

11 AM

6 PM

11 PM

4 AM

--°C/°C

Day time

Avg. Highest Time

5 AM - 6 AM

47AQI

2 hours / Day

60 hours / Month

Avg. Lowest Time

1 PM - 5 PM

38AQI

5 hours / Day

150 hours / Month

In the last 30 days, during the daytime, the highest AQI was between 5 AM to 6 AM (Avg. 47), while the lowest AQI was between 1 PM to 5 PM (Avg. 38).

Night time

Avg. Highest Time

12 AM - 11 PM

47AQI

10 hours / Day

300 hours / Month

Avg. Lowest Time

12 AM - 11 PM

47AQI

10 hours / Day

300 hours / Month

In the last 30 days, during the daytime, the highest AQI was between 12 AM to 11 PM (Avg. 47), while the lowest AQI was between 12 AM to 11 PM (Avg. 47).

2025 Days Vs Air Quality
Hoan Kiem District, Ha Noi, Vietnam

2025

14%

62%

160

22%

Total number of days with different AQI categories in last 261 days in 2025 (104 days remaining)

Good

36 Days

Moderate

160 Days

Poor

56 Days

Unhealthy

8 Days

Severe

0 Days

Hazardous

0 Days

Under WHO’s Safe Air Quality Limits: 14%

Health Risk Level:

Extreme

In 2025, 14% of 261 days were within WHO’s safe air quality limits. The risk of health issues is Extreme, potentially causing respiratory problems, heart disease, skin issues, and stress, especially for children, the elderly, and those with pre-existing conditions.

Annual Air Quality Insights
Hoan Kiem District, Ha Noi, Vietnam

AQI levels in 2025

AQI

PM2.5

PM10

SO2

NO2

Sun.Mon.Tue.Wed.Thu.Fri.Sat.

Jan.

Feb.

Mar.

Apr.

May

Jun.

Jul.

Aug.

Sep.

Oct.

Nov.

Dec.

132AQI

99AQI

95AQI

101AQI

68AQI

63AQI

59AQI

48AQI

46AQI

No. of days

Jan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.Total Days

202581AQI

160

Highest AQI recorded in

January

132AQI

Lowest AQI recorded in

September

46AQI

202467AQI

156

Highest AQI recorded in

December

99AQI

Lowest AQI recorded in

March

8AQI

2023104AQI

145

108

Highest AQI recorded in

January

164AQI

Lowest AQI recorded in

July

70AQI

2022138AQI

Highest AQI recorded in

October

155AQI

Lowest AQI recorded in

November

122AQI

Most & Least Polluted Years Over the Last 4 Years

Most Polluted Year Recorded

2022(Avg.)

138AQI

Least Polluted Year Recorded

2024(Avg.)

67AQI

Hoan Kiem District's annual 2025 AQI (81) shows an average percentage change of -14.4% (improved AQI) compared to previous years: 2022 (138), 2023 (104), 2024 (67).


5 AM	50
6 AM	50
7 AM	56
8 AM	68
9 AM	59
10 AM	62
11 AM	52
12 PM	43
1 PM	34
2 PM	43
3 PM	42
4 PM	42
5 PM	40
6 PM	43
7 PM	44
8 PM	54
9 PM	58
10 PM	58
11 PM	58
12 AM	56
1 AM	46
2 AM	44
3 AM	44
4 AM	48

Hoan Kiem District, Ha Noi, Vietnam Historical Air Quality Analysis

September Air Quality AnalysisHoan Kiem District, Ha Noi, Vietnam

Day & Night AQI Trend: 17th Sep - 18th Sep 2025Hoan Kiem District, Ha Noi, Vietnam

Day & Night AQI Trend : Aug - Sep 2025Hoan Kiem District, Ha Noi, Vietnam

2025 Days Vs Air Quality Hoan Kiem District, Ha Noi, Vietnam

Annual Air Quality InsightsHoan Kiem District, Ha Noi, Vietnam

AQI levels in 2025

No. of days

September Air Quality Analysis
Hoan Kiem District, Ha Noi, Vietnam

Day & Night AQI Trend: 17th Sep - 18th Sep 2025
Hoan Kiem District, Ha Noi, Vietnam

Day & Night AQI Trend : Aug - Sep 2025
Hoan Kiem District, Ha Noi, Vietnam

2025 Days Vs Air Quality
Hoan Kiem District, Ha Noi, Vietnam

Annual Air Quality Insights
Hoan Kiem District, Ha Noi, Vietnam