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. 1201PilsenPlzeň Region, Czechia 1%3 of 274
  2. 1202Ludweiler-Warndtlast full day 10 OctSaarland, Germany 1%3 of 274
  3. 1203BadgerAlaska, United States 1%3 of 274
  4. 1204LindenNew Jersey, United States 1%3 of 274
  5. 1205EdgewoodMaryland, United States 1%3 of 275
  6. 1206West FargoNorth Dakota, United States 1%3 of 275
  7. 1207MoabUtah, United States 1%3 of 275
  8. 1208Parry SoundOntario, Canada 1%3 of 275
  9. 1209HavreMontana, United States 1%3 of 275
  10. 1210FontanaCalifornia, United States 1%3 of 276
  11. 1211Dattelnlast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 276
  12. 1212WakefieldEngland, United Kingdom 1%3 of 276
  13. 1213EwingNew Jersey, United States 1%3 of 276
  14. 1214WarrenPennsylvania, United States 1%3 of 276
  15. 1215Holbrooklast full day 11 OctNew York, United States 1%3 of 276
  16. 1216StaytonOregon, United States 1%3 of 276
  17. 1217Unnalast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 277
  18. 1218PennsaukenNew Jersey, United States 1%3 of 277
  19. 1219VirginiaMinnesota, United States 1%3 of 277
  20. 1220AltoonaPennsylvania, United States 1%3 of 277
  21. 1221GreshamOregon, United States 1%3 of 277
  22. 1222TaibaoTaiwan, Taiwan 1%3 of 278
  23. 1223České BudějoviceSouth Bohemian Region, Czechia 1%3 of 278
  24. 1224CantonOhio, United States 1%3 of 278
  25. 1225Trostberg an der Alzlast full day 10 OctBavaria, Germany 1%3 of 278
  26. 1226GreensburgPennsylvania, United States 1%3 of 278
  27. 1227State CollegePennsylvania, United States 1%3 of 278
  28. 1228HermitagePennsylvania, United States 1%3 of 278
  29. 1229Weirton HeightsWest Virginia, United States 1%3 of 278
  30. 1230HalfwayMaryland, United States 1%3 of 278
  31. 1231Oregon CityOregon, United States 1%3 of 278
  32. =1232Jüchenlast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 279
  33. =1232ColumbusGeorgia, United States 1%3 of 279
  34. 1234HaguenauGrand Est, France 1%3 of 279
  35. 1235Michigan CityIndiana, United States 1%3 of 279
  36. 1236UniontownPennsylvania, United States 1%3 of 279
  37. 1237GreeleyColorado, United States 1%3 of 279
  38. 1238LewistownMontana, United States 1%3 of 279
  39. 1239WoodburnOregon, United States 1%3 of 279
  40. 1240Labrador CityNewfoundland and Labrador, Canada 1%3 of 279
  41. 1241ErlinTaiwan, Taiwan 1%3 of 280
  42. 1242IngolstadtBavaria, Germany 1%3 of 280
  43. 1243Neuenburg am RheinBaden-Wurttemberg, Germany 1%3 of 280
  44. 1244Ansbachlast full day 10 OctBavaria, Germany 1%3 of 280
  45. =1245UtrechtUtrecht, The Netherlands 1%3 of 280
  46. =1245Trierlast full day 10 OctRheinland-Pfalz, Germany 1%3 of 280
  47. 1247FilderstadtBaden-Wurttemberg, Germany 1%3 of 280
  48. 1248Kaldenkirchenlast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 280
  49. 1249NorristownPennsylvania, United States 1%3 of 280
  50. 1250Smithvillelast full day 9 OctNew Jersey, United States 1%3 of 280
  51. 1251Atlantic CityNew Jersey, United States 1%3 of 280
  52. 1252Sherwood ParkAlberta, Canada 1%3 of 280
  53. 1253BellevilleOntario, Canada 1%3 of 280
  54. 1254North BayOntario, Canada 1%3 of 280
  55. 1255SilvertonOregon, United States 1%3 of 280
  56. 1256Hagenlast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 281
  57. 1257Oberhausenlast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 281
  58. 1258Wismarlast full day 10 OctMecklenburg-Vorpommern, Germany 1%3 of 281
  59. 1259Otterndorflast full day 10 OctLower Saxony, Germany 1%3 of 281
  60. 1260AalenBaden-Wurttemberg, Germany 1%3 of 281
  61. 1261Baden-BadenBaden-Wurttemberg, Germany 1%3 of 281
  62. 1262Drayton ValleyAlberta, Canada 1%3 of 281
  63. 1263PalmyraNew Jersey, United States 1%3 of 282
  64. 1264Gelsenkirchenlast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 282
  65. 1265Duisburglast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 282
  66. 1266Essenlast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 282
  67. 1267SocorroTexas, United States 1%3 of 282
  68. 1268Schwertelast full day 10 OctNorth Rhine-Westphalia, Germany 1%3 of 282
  69. 1269ErtveldeFlanders, Belgium 1%3 of 282
  70. 1270Eggenstein-LeopoldshafenBaden-Wurttemberg, Germany 1%3 of 282
  71. =1271ClaymontDelaware, United States 1%3 of 282
  72. =1271MonessenPennsylvania, United States 1%3 of 282
  73. 1273Saint PaulMinnesota, United States 1%3 of 282
  74. 1274BridgevillePennsylvania, United States 1%3 of 282
  75. 1275Tri-CitiesWashington, United States 1%3 of 282
  76. 1276North BendWashington, United States 1%3 of 282
  77. 1277GwangyangJeollanam-do, South Korea 1%3 of 283
  78. 1278RiversideCalifornia, United States 1%3 of 283
  79. 1279ValdostaGeorgia, United States 1%3 of 283
  80. 1280Kennedy TownshipPennsylvania, United States 1%3 of 283
  81. 1281GlendoraCalifornia, United States 1%3 of 283
  82. 1282TecumsehMichigan, United States 1%3 of 283
  83. 1283Cleveland HeightsOhio, United States 1%3 of 283
  84. 1284BeauvaisHauts-de-France, France 1%3 of 283
  85. 1285ChathamOntario, Canada 1%3 of 283
  86. =1286Kennett SquarePennsylvania, United States 1%3 of 283
  87. =1286Jefferson HillsPennsylvania, United States 1%3 of 283
  88. 1288Toms RiverNew Jersey, United States 1%3 of 283
  89. 1289BarabooWisconsin, United States 1%3 of 283
  90. 1290Medicine HatAlberta, Canada 1%3 of 283
  91. 1291Cottage GroveOregon, United States 1%3 of 283
  92. 1292TigardOregon, United States 1%3 of 283
  93. 1293NaesŏGyeongsangnam-do, South Korea 1%3 of 284
  94. 1294DaytonOhio, United States 1%3 of 284
  95. 1295WilkinsburgPennsylvania, United States 1%3 of 284
  96. =1296BeverenFlanders, Belgium 1%3 of 284
  97. =1296PittsburghPennsylvania, United States 1%3 of 284
  98. =1296LemwerderLower Saxony, Germany 1%3 of 284
  99. 1299RitterhudeLower Saxony, Germany 1%3 of 284
  100. 1300WillebroekFlanders, Belgium 1%3 of 284

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

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).