SmogRank / Rankings

All 3,290 cities by unhealthy days, last 30 days

Every city with enough measurements in this window, worst first.

CPCB in India: no readings since 12 Oct (488 monitors). EEA in Spain: no readings since 13 Oct (310 monitors). Their cities show older figures or are missing from this board, not clean.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Cities with the same share are ordered by more unhealthy days, then by the higher average.

  1. =399Milanlast full day 11 OctLombardy, Italy 0%0 of 28
  2. =399CalamaAntofagasta, Chile 0%0 of 21
  3. =403BangkokBangkok, Thailand 0%0 of 30
  4. =403PuliTaiwan, Taiwan 0%0 of 30
  5. =403GunsanJeollabuk-do, South Korea 0%0 of 29
  6. =406TaibaoTaiwan, Taiwan 0%0 of 30
  7. =406TainanTaiwan, Taiwan 0%0 of 30
  8. =406Rio ClaroSão Paulo, Brazil 0%0 of 29
  9. =406NilópolisRio de Janeiro, Brazil 0%0 of 30
  10. =410IksanJeollabuk-do, South Korea 0%0 of 29
  11. =410HongseongChungcheongnam-do, South Korea 0%0 of 29
  12. =410Ciudad NezahualcoyotlMéxico, Mexico 0%0 of 30
  13. =413MukdahanMukdahan, Thailand 0%0 of 30
  14. =413NajuJeollanam-do, South Korea 0%0 of 29
  15. =413SevillaAndalusia, Spain 0%0 of 30
  16. =416TaichungTaiwan, Taiwan 0%0 of 30
  17. =416Poggio Ruscolast full day 11 OctLombardy, Italy 0%0 of 24
  18. =416Novi SadVojvodina, Serbia 0%0 of 30
  19. =416Bijelo PoljeBijelo Polje, Montenegro 0%0 of 30
  20. =416Alto Hospiciolast full day 11 OctTarapacá, Chile 0%0 of 26
  21. =421San Tung Chung HangIslands, Hong Kong 0%0 of 28
  22. =421YeonggwangJeollanam-do, South Korea 0%0 of 29
  23. =421GwangmyeongGyeonggi-do, South Korea 0%0 of 30
  24. =424KikindaVojvodina, Serbia 0%0 of 30
  25. =424Mong KokYau Tsim Mong District, Hong Kong 0%0 of 30
  26. =424FanlingNorth District, Hong Kong 0%0 of 29
  27. =424AccraGreater Accra, Ghana 0%0 of 28
  28. =424FreetownWestern Area, Sierra Leone 0%0 of 22
  29. =429BārmerRajasthan, India 0%0 of 24
  30. =429XinyingTaiwan, Taiwan 0%0 of 30
  31. =429NantouTaiwan, Taiwan 0%0 of 30
  32. =429LuguTaiwan, Taiwan 0%0 of 30
  33. =429OkcheonNorth Chungcheong, South Korea 0%0 of 30
  34. =429Ganghwa-gunIncheon, South Korea 0%0 of 29
  35. =429KłodzkoLower Silesia, Poland 0%0 of 28
  36. =429PueblaPuebla, Mexico 0%0 of 30
  37. =429TlaquepaqueJalisco, Mexico 0%0 of 22
  38. =438DurgChhattisgarh, India 0%0 of 26
  39. =438Ban Khlong PrawetBangkok, Thailand 0%0 of 30
  40. =438FengshanTakao, Taiwan 0%0 of 30
  41. =438Chiayi CityTaiwan, Taiwan 0%0 of 30
  42. =442YŏnmuChungcheongnam-do, South Korea 0%0 of 28
  43. =442San Pedro SulaCortés Department, Honduras 0%0 of 30
  44. =442HanfordCalifornia, United States 0%0 of 30
  45. =445MuanJeollanam-do, South Korea 0%0 of 30
  46. =445IncheonIncheon, South Korea 0%0 of 30
  47. =445ChanghuaTaiwan, Taiwan 0%0 of 30
  48. =445NovaraPiedmont, Italy 0%0 of 27
  49. =445BraPiedmont, Italy 0%0 of 30
  50. =450DebrecenHajdú-Bihar, Hungary 0%0 of 30
  51. =450NišCentral Serbia, Serbia 0%0 of 30
  52. =450Icheon-siGyeonggi-do, South Korea 0%0 of 29
  53. =450CheorwonGangwon-do, South Korea 0%0 of 30
  54. =454SkopjeGrad Skopje, North Macedonia 0%0 of 30
  55. =454Bang PakongChachoengsao, Thailand 0%0 of 30
  56. =454WrocławLower Silesia, Poland 0%0 of 30
  57. =454CorcoranCalifornia, United States 0%0 of 30
  58. =454Bueng KumBangkok, Thailand 0%0 of 30
  59. =459Tai PoTai Po, Hong Kong 0%0 of 30
  60. =459NamsaJeollabuk-do, South Korea 0%0 of 28
  61. =459WłocławekKujawsko-Pomorskie, Poland 0%0 of 30
  62. =459TurinPiedmont, Italy 0%0 of 30
  63. =463RayongRayong, Thailand 0%0 of 25
  64. =463Nakhon PathomNakhon Pathom, Thailand 0%0 of 29
  65. =463XizhiTaipei, Taiwan 0%0 of 30
  66. =463ZhongliaoTaiwan, Taiwan 0%0 of 30
  67. =463Sham Shui PoSham Shui Po District, Hong Kong 0%0 of 30
  68. =463Kwai ChungKwai Tsing District, Hong Kong 0%0 of 30
  69. =469KaohsiungTakao, Taiwan 0%0 of 30
  70. =469Guri-siGyeonggi-do, South Korea 0%0 of 30
  71. =469GumiGyeongsangbuk-do, South Korea 0%0 of 30
  72. =469Goyang-siGyeonggi-do, South Korea 0%0 of 29
  73. =469Ansan-siGyeonggi-do, South Korea 0%0 of 30
  74. =474Sighetu Marmaţieilast full day 10 OctMaramureş, Romania 0%0 of 24
  75. =474ZamośćLublin, Poland 0%0 of 30
  76. =474Ban Talat BuengChon Buri, Thailand 0%0 of 30
  77. =474YongkangTaiwan, Taiwan 0%0 of 30
  78. =474Jastrzębie ZdrójSilesia, Poland 0%0 of 30
  79. =474SoachaCundinamarca, Colombia 0%0 of 30
  80. =474Jurupa ValleyCalifornia, United States 0%0 of 30
  81. =481PinetownKwaZulu-Natal, South Africa 0%0 of 27
  82. =481TratTrat, Thailand 0%0 of 30
  83. =481OsanGyeonggi-do, South Korea 0%0 of 30
  84. =481ZiguinchorZiguinchor, Senegal 0%0 of 30
  85. =481KoprivnicaKoprivnica-Križevci, Croatia 0%0 of 30
  86. =486Craiovalast full day 10 OctDolj, Romania 0%0 of 27
  87. =486StarachowiceŚwiętokrzyskie, Poland 0%0 of 30
  88. =486XizhouTaiwan, Taiwan 0%0 of 30
  89. =486Sau Mau PingKwun Tong District, Hong Kong 0%0 of 30
  90. =486EisenGyeongsangbuk-do, South Korea 0%0 of 29
  91. =486KoesanNorth Chungcheong, South Korea 0%0 of 30
  92. =486ToledoCastille-La Mancha, Spain 0%0 of 30
  93. =486FunzaCundinamarca, Colombia 0%0 of 28
  94. =486ClovisCalifornia, United States 0%0 of 30
  95. =495Gostivarlast full day 10 OctGostivar, North Macedonia 0%0 of 25
  96. =495ShakaskraalKwaZulu-Natal, South Africa 0%0 of 30
  97. =495KohimaNagaland, India 0%0 of 24
  98. =495ChaozhouTaiwan, Taiwan 0%0 of 30
  99. =495BoryeongChungcheongnam-do, South Korea 0%0 of 29
  100. =495MasanGwangju, South Korea 0%0 of 30

What stands behind each figure: Checked at 2+ sites One reference monitor Low-cost sensors About these marks

Low-cost sensors: consumer units, counted only in cities with no government-grade monitor; they read close to reference monitors on the whole, but 15 to 25% high in humid air. How we use them.

Good0–50
Moderate51–100
Unhealthy for sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Not covered: the government monitoring networks of China, Turkey and Iran, which publish only on their own websites. We are building the reader for China's network. The networks of Turkey and Iran don't answer requests from outside their countries, so we can't read them. Most cities there are missing from this board, not clean. Why.

Use this board

SmogRank, all cities ranked by unhealthy days (PM2.5), last 30 days to 14 Oct 2026, 07:00 UTC: each city's share of its measured days with a daily mean over 35.4 µg/m³, cities measured on 21 or more of the 30 days. Monitor data from national networks via OpenAQ and the publishers listed at smogrank.com/sources. smogrank.com/rankings?w=30d&by=days. Ranked on low-cost sensors, with no reference monitor in the city: #1 Peshawar, #2 Multan, #5 Kasur, #7 Gujranwala, #8 Lahore, #9 Faisalabad and #10 Jammu. Some values from Sensor.Community, ODbL. Some readings from Vietnam's government monitors; Department of Environment, Nepal; Aurassure; RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver); Umhverfisstofnun (Environment Agency of Iceland), no reuse terms published.

Download top 10 by average (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Updated 2026-10-14 07:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Vietnam's government monitors; Department of Environment, Nepal; Aurassure; RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver); Umhverfisstofnun (Environment Agency of Iceland), no reuse terms published (why we use them).