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. 3185PeterboroughOntario, Canada 0%0 of 23
  2. =3202Saint-DenisReunion, Reunion 0%0 of 27
  3. =3202EupenWallonia, Belgium 0%0 of 30
  4. =3202North ChicopeeMassachusetts, United States 0%0 of 30
  5. =3202Newburghlast full day 11 OctNew York, United States 0%0 of 28
  6. =3202BenningtonVermont, United States 0%0 of 29
  7. =3202AlamosaColorado, United States 0%0 of 28
  8. =3202FairbanksAlaska, United States 0%0 of 30
  9. =3202North CowichanBritish Columbia, Canada 0%0 of 26
  10. =3210Narvalast full day 10 OctIda-Virumaa, Estonia 0%0 of 26
  11. =3210SakaiminatoTottori, Japan 0%0 of 30
  12. =3210Newton AbbotEngland, United Kingdom 0%0 of 30
  13. =3210ÖrnsköldsvikVästernorrland, Sweden 0%0 of 28
  14. =3210HamoisWallonia, Belgium 0%0 of 30
  15. =3210RockvilleMaryland, United States 0%0 of 26
  16. =3210LewistonMaine, United States 0%0 of 29
  17. =3210CheneyWashington, United States 0%0 of 30
  18. =3210Fort McMurrayAlberta, Canada 0%0 of 30
  19. =3210FrederictonNew Brunswick, Canada 0%0 of 30
  20. =3210MonctonNew Brunswick, Canada 0%0 of 30
  21. =3210Grand CentreAlberta, Canada 0%0 of 30
  22. =3222JyväskyläCentral Finland, Finland 0%0 of 30
  23. =3222AlicanteValencia, Spain 0%0 of 27
  24. =3222InvernessScotland, United Kingdom 0%0 of 30
  25. =3222CambridgeMaryland, United States 0%0 of 29
  26. =3222BangorMaine, United States 0%0 of 30
  27. =3222AltoonaPennsylvania, United States 0%0 of 28
  28. =3222Casas AdobesArizona, United States 0%0 of 29
  29. =3222Green ValleyArizona, United States 0%0 of 30
  30. =3222Big Bear CityCalifornia, United States 0%0 of 29
  31. =3222TaosNew Mexico, United States 0%0 of 30
  32. =3222MesquiteNevada, United States 0%0 of 30
  33. =3222Steamboat SpringsColorado, United States 0%0 of 28
  34. =3222KentvilleNova Scotia, Canada 0%0 of 30
  35. =3222Parry SoundOntario, Canada 0%0 of 30
  36. =3222Port WallaceNova Scotia, Canada 0%0 of 29
  37. =3222Oxon Hill-GlassmanorMaryland, United States 0%0 of 30
  38. =3238Cañon CityColorado, United States 0%0 of 28
  39. =3238Boulder CityNevada, United States 0%0 of 30
  40. =3238CorvallisOregon, United States 0%0 of 28
  41. =3238DallasOregon, United States 0%0 of 27
  42. =3238RedmondOregon, United States 0%0 of 28
  43. =3238RivertonWyoming, United States 0%0 of 27
  44. =3238PalmerAlaska, United States 0%0 of 30
  45. =3238CharlottetownPrince Edward Island, Canada 0%0 of 30
  46. =3238Rouyn-NorandaQuebec, Canada 0%0 of 30
  47. =3238Sydneylast full day 11 OctNova Scotia, Canada 0%0 of 23
  48. =3248TamperePirkanmaa, Finland 0%0 of 30
  49. =3248PenicuikScotland, United Kingdom 0%0 of 30
  50. =3248AberdeenSouth Dakota, United States 0%0 of 21
  51. =3248AspenColorado, United States 0%0 of 28
  52. =3248NewportOregon, United States 0%0 of 28
  53. =3248Hawaiian Paradise ParkHawaii, United States 0%0 of 29
  54. =3248MiramichiNew Brunswick, Canada 0%0 of 30
  55. =3248Sault Ste. MarieOntario, Canada 0%0 of 26
  56. =3256Tallinnlast full day 10 OctHarjumaa, Estonia 0%0 of 27
  57. =3256Kohtla-Järvelast full day 9 OctIda-Virumaa, Estonia 0%0 of 26
  58. =3256KuopioNorth Savo, Finland 0%0 of 30
  59. =3256Mount Ivylast full day 11 OctNew York, United States 0%0 of 26
  60. =3256GreenOregon, United States 0%0 of 27
  61. =3256CodyWyoming, United States 0%0 of 30
  62. =3262SaltashEngland, United Kingdom 0%0 of 30
  63. =3262BertrixWallonia, Belgium 0%0 of 30
  64. =3262ReykjavíkCapital Region, Iceland 0%0 of 30
  65. =3262South LaurelMaryland, United States 0%0 of 29
  66. =3262White Plainslast full day 11 OctNew York, United States 0%0 of 28
  67. =3262AnacortesWashington, United States 0%0 of 30
  68. =3262RanchettesWyoming, United States 0%0 of 29
  69. =3269MiddletonWisconsin, United States 0%0 of 21
  70. =3269HavreMontana, United States 0%0 of 29
  71. =3269RawlinsWyoming, United States 0%0 of 30
  72. =3272HortaAzores, Portugal 0%0 of 30
  73. =3272Rock SpringsWyoming, United States 0%0 of 27
  74. =3274DerryNorthern Ireland, United Kingdom 0%0 of 28
  75. =3274Angra do HeroísmoAzores, Portugal 0%0 of 30
  76. =3274WorlandWyoming, United States 0%0 of 30
  77. =3274West GreenwichRhode Island, United States 0%0 of 26
  78. =3278ÖstersundJämtland, Sweden 0%0 of 28
  79. =3278CouvinWallonia, Belgium 0%0 of 27
  80. =3278LaconiaNew Hampshire, United States 0%0 of 30
  81. =3278LaramieWyoming, United States 0%0 of 30
  82. 3282LanderWyoming, United States 0%0 of 29
  83. =3283GarðabærCapital Region, Iceland 0%0 of 30
  84. =3283Brookingslast full day 7 OctOregon, United States 0%0 of 24
  85. 3285Petite-ÎleReunion, Reunion 0%0 of 30
  86. 3286Labrador CityNewfoundland and Labrador, Canada 0%0 of 30
  87. 3287UmeåVästerbotten, Sweden 0%0 of 24
  88. =3288Sweet HomeOregon, United States 0%0 of 28
  89. =3288Ponta DelgadaAzores, Portugal 0%0 of 29
  90. 3290YellowknifeNorthwest Territories, Canada 0%0 of 24

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).