SmogRank / Rankings

All 3,198 cities by unhealthy days, this year

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. 701SpokaneWashington, United States 3%10 of 286
  2. 702PendletonOregon, United States 3%10 of 286
  3. 703San Pawl il-BaħarSaint Paul’s Bay, Malta 3%7 of 202
  4. 704HwacheonGangwon-do, South Korea 3%9 of 264
  5. 705LeibnitzStyria, Austria 3%9 of 267
  6. 706YeonggwangJeollanam-do, South Korea 3%9 of 268
  7. 707RedmondOregon, United States 3%9 of 268
  8. 708Spokane ValleyWashington, United States 3%9 of 269
  9. 709Liberty LakeWashington, United States 3%9 of 272
  10. 710ŻabbarĦaż-Żabbar, Malta no daily values yet3%7 of 213
  11. 711BardejovPrešov Region, Slovakia 3%9 of 274
  12. 712KaiapoiCanterbury, New Zealand 3%9 of 276
  13. 713Halstenbeklast full day 10 OctSchleswig-Holstein, Germany 3%9 of 276
  14. 714Tin Shui WaiYuen Long, Hong Kong 3%7 of 216
  15. 715GyeongjuGyeongsangbuk-do, South Korea 3%9 of 278
  16. 716Bitterfeld-Wolfenlast full day 10 OctSaxony-Anhalt, Germany 3%9 of 278
  17. 717DouliuTaiwan, Taiwan 3%9 of 281
  18. 718Blankenfelde-Mahlowlast full day 10 OctBrandenburg, Germany 3%9 of 281
  19. 719Halberstadtlast full day 10 OctSaxony-Anhalt, Germany 3%9 of 281
  20. 720Osternienburger Landlast full day 10 OctSaxony-Anhalt, Germany 3%9 of 281
  21. 721Hannoverlast full day 10 OctLower Saxony, Germany 3%9 of 281
  22. 722Walla WallaWashington, United States 3%9 of 281
  23. 723Bad Frankenhausenlast full day 10 OctThuringia, Germany 3%9 of 282
  24. 724Wernigerodelast full day 10 OctSaxony-Anhalt, Germany 3%9 of 282
  25. 725Columbia FallsMontana, United States 3%9 of 282
  26. 726MexicaliBaja California, Mexico 3%9 of 283
  27. 727Szczytnalast full day 11 OctLower Silesia, Poland 3%9 of 283
  28. 728NeubrandenburgMecklenburg-Vorpommern, Germany 3%9 of 284
  29. 729Bernau bei BerlinBrandenburg, Germany 3%9 of 284
  30. 730Dallgow-DöberitzBrandenburg, Germany 3%9 of 284
  31. 731SinanJeollanam-do, South Korea 3%8 of 253
  32. 732DimitrovgradHaskovo, Bulgaria 3%9 of 285
  33. 733KimhaeGyeongsangnam-do, South Korea 3%9 of 286
  34. 734PraguePrague, Czechia 3%9 of 286
  35. 735BakersfieldCalifornia, United States 3%9 of 286
  36. 736Novo MestoUrban Municipality of Novo Mesto, Slovenia 3%9 of 286
  37. 737T’aebaekGangwon-do, South Korea 3%8 of 255
  38. 738BeerselFlanders, Belgium 3%8 of 255
  39. 739Santa Maria A VicoCampania, Italy 3%8 of 256
  40. 740KelownaBritish Columbia, Canada 3%7 of 225
  41. 741Barthlast full day 10 OctMecklenburg-Vorpommern, Germany 3%8 of 260
  42. 742Cava Dè TirreniCampania, Italy 3%8 of 262
  43. 743GangneungGangwon-do, South Korea 3%8 of 266
  44. 744San Tung Chung HangIslands, Hong Kong 3%6 of 201
  45. 745Williams LakeBritish Columbia, Canada 3%8 of 271
  46. 746RuseRuse, Bulgaria 3%8 of 274
  47. 747Fürstenberglast full day 10 OctBrandenburg, Germany 3%8 of 277
  48. 748Twin FallsIdaho, United States 3%8 of 277
  49. 749Coeur d'AleneIdaho, United States 3%8 of 279
  50. 750JinchengFukien, Taiwan 3%8 of 280
  51. 751SereďTrnava Region, Slovakia 3%8 of 280
  52. 752Wormslast full day 10 OctRheinland-Pfalz, Germany 3%8 of 280
  53. 753LitvínovÚstí nad Labem Region, Czechia 3%8 of 281
  54. 754PardubicePardubice Region, Czechia 3%8 of 281
  55. 755Bösellast full day 10 OctLower Saxony, Germany 3%8 of 281
  56. 756RokycanyPlzeň Region, Czechia 3%8 of 281
  57. 757Braunschweiglast full day 10 OctLower Saxony, Germany 3%8 of 281
  58. 758Wolfsburglast full day 10 OctLower Saxony, Germany 3%8 of 281
  59. 759Popeşti-Leordenilast full day 10 OctIlfov, Romania 3%8 of 282
  60. 760Weimarlast full day 10 OctThuringia, Germany 3%8 of 282
  61. 761TongyeongGyeongsangnam-do, South Korea 3%7 of 247
  62. 762Duque de CaxiasRio de Janeiro, Brazil 3%8 of 283
  63. 763Donghae CityGangwon-do, South Korea 3%8 of 284
  64. 764PartizánskeTrenčín Region, Slovakia 3%8 of 284
  65. 765WolfsbergCarinthia, Austria 3%8 of 285
  66. 766BrnoSouth Moravian, Czechia 3%8 of 286
  67. 767MariborUrban Municipality of Maribor, Slovenia 3%8 of 286
  68. 768CalgaryAlberta, Canada 3%8 of 286
  69. 769Kwai ChungKwai Tsing District, Hong Kong 3%6 of 217
  70. 770Sham Shui PoSham Shui Po District, Hong Kong 3%6 of 218
  71. 771KosongGangwon-do, South Korea 3%7 of 256
  72. 772JumunjinGangwon-do, South Korea 3%7 of 260
  73. 773ZnojmoSouth Moravian, Czechia 3%6 of 225
  74. 774MedemblikNorth Holland, The Netherlands 3%7 of 263
  75. 775JangseongJeollanam-do, South Korea 3%7 of 264
  76. 776Fürstenfeldlast full day 24 SeptStyria, Austria 3%7 of 267
  77. 777Schöneichelast full day 10 OctBrandenburg, Germany 3%7 of 267
  78. 778BeneventoCampania, Italy 3%7 of 268
  79. 779LiberpolisCounty of Osijek-Baranja, Croatia 3%7 of 268
  80. 780Murcialast full day 11 OctMurcia, Spain 3%6 of 232
  81. 781Bad Kreuznachlast full day 10 OctRheinland-Pfalz, Germany 3%6 of 232
  82. 782BadhoevedorpNorth Holland, The Netherlands 3%6 of 232
  83. 783MostaIl-Mosta, Malta 3%7 of 271
  84. 784MissoulaMontana, United States 3%7 of 274
  85. 785SokchoGangwon-do, South Korea 3%7 of 275
  86. 786Hildesheimlast full day 10 OctLower Saxony, Germany 3%7 of 275
  87. 787ErlunTaiwan, Taiwan 3%7 of 276
  88. 788SchwerinMecklenburg-Vorpommern, Germany 3%7 of 276
  89. 789Salzgitterlast full day 10 OctLower Saxony, Germany 3%7 of 277
  90. 790PassyAuvergne-Rhône-Alpes, France 3%7 of 278
  91. 791Boulogne-sur-MerHauts-de-France, France 3%7 of 278
  92. 792AgassizBritish Columbia, Canada 3%7 of 278
  93. 793YangsanGyeongsangnam-do, South Korea 3%7 of 280
  94. 794DunaújvárosFejér, Hungary 3%7 of 280
  95. 795BiellaPiedmont, Italy 3%6 of 240
  96. 796Elsterwerdalast full day 10 OctBrandenburg, Germany 2%7 of 281
  97. 797Ludwigslustlast full day 10 OctMecklenburg-Vorpommern, Germany 2%7 of 281
  98. 798Eisenachlast full day 10 OctThuringia, Germany 2%7 of 281
  99. 799Bucharestlast full day 10 OctBucharest, Romania 2%7 of 282
  100. 800Dortmundlast full day 10 OctNorth Rhine-Westphalia, Germany 2%7 of 282

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), this year 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 70% or more of the days since 1 January (at least 14). Monitor data from national networks via OpenAQ and the publishers listed at smogrank.com/sources. smogrank.com/rankings?w=year&by=days. Ranked on low-cost sensors, with no reference monitor in the city: #4 Kampala and #8 Faisalabad. Some values from Sensor.Community, ODbL. Some readings from Department of Environment, Nepal; Vietnam's government monitors; Aurassure; RMCAB (Secretaría Distrital de Ambiente, Bogotá); 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: Department of Environment, Nepal; Vietnam's government monitors; Aurassure; RMCAB (Secretaría Distrital de Ambiente, Bogotá); Umhverfisstofnun (Environment Agency of Iceland), no reuse terms published (why we use them).