SmogRank / History / August 4, 2025

Most polluted cities on August 4, 2025

2,545 cities ranked by their average PM2.5 over the day; the worst was Coyhaique, Chile, at 148.5 µg/m³. Each city's own local calendar day.

Bad-air episodes during August 4, 2025. All episodes.

← Coyhaique 148.5 µg/m³ 100 µg/m³15 WHO 24-hour guideline
Every city ranked for August 4, 2025, one column each, worst on the left and cleanest on the right; height is PM2.5 in µg/m³. Point at it to read a city; tap to open it.
  1. 1CoyhaiqueAysén, Chile
    2249.9×
  2. 2OsornoLos Lagos Region, Chile
    2149.3×
  3. 3NagapattinamTamil Nadu, India
    2098.9×
  4. 4DhaulpurRajasthan, India
    2038.5×
  5. 5Fort McMurrayAlberta, Canada
    1957.8×
  6. 6NacimientoBiobio, Chile
    1887.2×
  7. 7Puerto VarasLos Lagos Region, Chile
    1846.8×
  8. 8Sri GanganagarRajasthan, India
    1806.5×
  9. 9VillarricaAraucania, Chile
    1766.1×
  10. 10KigaliKigali, Rwanda
    1725.7×
  11. 11Puerto MonttLos Lagos Region, Chile
    1685.3×
  12. 12ChāpraBihar, India
    1665.1×
  13. 13TemucoAraucania, Chile
    1624.8×
  14. 14RancaguaO'Higgins Region, Chile
    1594.5×
  15. 15ChillánÑuble, Chile
    1594.5×
  16. 16RamanathapuramTamil Nadu, India
    1574.3×
  17. 17ManamaManama, Bahrain
    1564.2×
  18. 17LondonOntario, Canada
    1564.2×
  19. 19SarniaOntario, Canada
    1564.2×
  20. 20ValdiviaLos Ríos Region, Chile
    1564.1×
  21. 21WindsorOntario, Canada
    1554.1×
  22. 22KitchenerOntario, Canada
    1544.0×
  23. 23BrantfordOntario, Canada
    1544.0×
  24. 23UnderaGujarat, India
    1544.0×
  25. 25Port HuronMichigan, United States
    1533.9×
  26. 26HualpénBiobio, Chile
    1533.9×
  27. 27CuranilahueBiobio, Chile
    1533.9×
  28. 28Green BayWisconsin, United States
    1533.9×
  29. 29GuelphOntario, Canada
    1523.8×
  30. 30Bihār SharīfBihar, India
    1523.8×
  31. 31DetroitMichigan, United States
    1513.7×
  32. 31SouthfieldMichigan, United States
    1513.7×
  33. 33St. ThomasOntario, Canada
    1513.7×
  34. 34HamiltonOntario, Canada
    1503.7×
  35. 35DearbornMichigan, United States
    1463.6×
  36. 35MiltonOntario, Canada
    1463.6×
  37. 37EriePennsylvania, United States
    1453.6×
  38. 38ChathamOntario, Canada
    1443.5×
  39. 39La UniónLos Ríos Region, Chile
    1433.5×
  40. 40OakvilleOntario, Canada
    1423.5×
  41. 41EastpointeMichigan, United States
    1413.4×
  42. 42Bay CityMichigan, United States
    1403.4×
  43. 42AppletonWisconsin, United States
    1403.4×
  44. 44BellevilleOntario, Canada
    1393.4×
  45. 44WaterdownOntario, Canada
    1393.4×
  46. 46BuffaloNew York, United States
    1373.3×
  47. 47Oconomowoclow-cost sensorsWisconsin, United States
    1363.3×
  48. 48Lincoln ParkMichigan, United States
    1363.3×
  49. 49TalaganteSantiago Metropolitan, Chile
    1353.3×
  50. 50TorontoOntario, Canada
    1353.3×
  51. 51TalcahuanoBiobio, Chile
    1343.3×
  52. 52Shakaskraallow-cost sensorsKwaZulu-Natal, South Africa
    1343.2×
  53. 53MississaugaOntario, Canada
    1333.2×
  54. 53NewmarketOntario, Canada
    1333.2×
  55. 55TaylorMichigan, United States
    1323.2×
  56. 56BramptonOntario, Canada
    1313.2×
  57. 57QuilpuéValparaiso, Chile
    1313.2×
  58. 57BarrieOntario, Canada
    1313.2×
  59. 59KingstonOntario, Canada
    1303.1×
  60. 60BaddiHimachal Pradesh, India
    1303.1×
  61. 61MuzaffarnagarUttar Pradesh, India
    1293.1×
  62. 62RedfordMichigan, United States
    1283.1×
  63. 63ChāndaMaharashtra, India
    1283.1×
  64. 64RochesterNew York, United States
    1273.1×
  65. 64PeterboroughOntario, Canada
    1273.1×
  66. 66MalegaonMaharashtra, India
    1263.0×
  67. 67SyracuseNew York, United States
    1253.0×
  68. 68AurangābādBihar, India
    1243.0×
  69. 68AllistonOntario, Canada
    1243.0×
  70. 70LudhianaPunjab, India
    1233.0×
  71. 71MothīhāriBihar, India
    1233.0×
  72. 72DorvalQuebec, Canada
    1222.9×
  73. 73Nepeanlow-cost sensorsOntario, Canada
    1222.9×
  74. 74Puerto AysénAysén, Chile
    1202.9×
  75. 74YpsilantiMichigan, United States
    1202.9×
  76. 76HualquiBiobio, Chile
    1192.9×
  77. 77CoronelBiobio, Chile
    1192.9×
  78. 77AlbanyNew York, United States
    1192.9×
  79. 79AnantapurAndhra Pradesh, India
    1192.8×
  80. 80RengoO'Higgins Region, Chile
    1182.8×
  81. 81RasapūdipalemAndhra Pradesh, India
    1182.8×
  82. 82Gujranwalalow-cost sensorsPunjab, Pakistan
    1172.8×
  83. 83SantiagoSantiago Metropolitan, Chile
    1162.8×
  84. 83St. CatharinesOntario, Canada
    1162.8×
  85. 85CornwallOntario, Canada
    1162.8×
  86. 86DausaRajasthan, India
    1152.7×
  87. 86ScrantonPennsylvania, United States
    1152.7×
  88. 88JodaOdisha, India
    1142.7×
  89. 89Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    1132.7×
  90. 90TalcaMaule Region, Chile
    1122.7×
  91. 90WaukeshaWisconsin, United States
    1122.7×
  92. 92NandedMaharashtra, India
    1112.6×
  93. 92Temalow-cost sensorsGreater Accra, Ghana
    1112.6×
  94. 92BhiwadiRajasthan, India
    1112.6×
  95. 95MadisonWisconsin, United States
    1112.6×
  96. 96GranbyQuebec, Canada
    1112.6×
  97. 97ChittoorAndhra Pradesh, India
    1102.6×
  98. 97Grand RapidsMichigan, United States
    1102.6×
  99. 97LansingMichigan, United States
    1102.6×
  100. 100TonkRajasthan, India
    1102.6×
  101. 101MilwaukeeWisconsin, United States
    1102.6×
  102. 102Iloilolow-cost sensorsWestern Visayas, Philippines
    1092.6×
  103. 103Los ÁngelesBiobio, Chile
    1092.6×
  104. 104SaugorMadhya Pradesh, India
    1082.6×
  105. 104ToledoOhio, United States
    1082.6×
  106. 106JaipurRajasthan, India
    1082.6×
  107. 107GhāziābādUttar Pradesh, India
    1072.5×
  108. 108Puente AltoSantiago Metropolitan, Chile
    1072.5×
  109. 108Prince AlbertSaskatchewan, Canada
    1072.5×
  110. 110BuxarBihar, India
    1072.5×
  111. 111Ann Arborlow-cost sensorsMichigan, United States
    1062.5×
  112. 112KalyānMaharashtra, India
    1062.5×
  113. 113Islamabadlow-cost sensorsIslamabad, Pakistan
    1062.5×
  114. 113MontréalQuebec, Canada
    1062.5×
  115. 115MankatoMinnesota, United States
    1052.5×
  116. 116VijayawadaAndhra Pradesh, India
    1052.5×
  117. 118NalbāriAssam, India
    1042.4×
  118. 119Lahorelow-cost sensorsPunjab, Pakistan
    1042.4×
  119. 120LinaresMaule Region, Chile
    1032.4×
  120. 121PainesvilleOhio, United States
    1032.4×
  121. 122VrindāvanUttar Pradesh, India
    1022.4×
  122. 122KadapaAndhra Pradesh, India
    1022.4×
  123. 122BrossardQuebec, Canada
    1022.4×
  124. 125PittsfieldMassachusetts, United States
    1022.4×
  125. 126JhānsiUttar Pradesh, India
    1012.4×
  126. 127South MilwaukeeWisconsin, United States
    1002.4×
  127. 127SuperiorWisconsin, United States
    1002.4×
  128. 129Rawalpindilow-cost sensorsPunjab, Pakistan
    1002.4×
  129. 129San Francisco De BorjaLima region, Peru
    1002.4×
  130. 131BawānaDelhi, India
    992.3×
  131. 131BangorMaine, United States
    992.3×
  132. 133Lexingtonlow-cost sensorsMassachusetts, United States
    992.3×
  133. 134AyaseKanagawa, Japan
    992.3×
  134. 135GummidipundiTamil Nadu, India
    992.3×
  135. 135RutlandVermont, United States
    992.3×
  136. 135Sault Ste. MarieOntario, Canada
    992.3×
  137. 138ClevelandOhio, United States
    982.3×
  138. 138Greater NoidaUttar Pradesh, India
    982.3×
  139. 138SingrauliMadhya Pradesh, India
    982.3×
  140. 141Cleveland HeightsOhio, United States
    982.3×
  141. 142SherbrookeQuebec, Canada
    972.3×
  142. 143BānswāraRajasthan, India
    972.3×
  143. 143IwataShizuoka, Japan
    972.3×
  144. 143Eau ClaireWisconsin, United States
    972.3×
  145. 143MandideepMadhya Pradesh, India
    972.3×
  146. 147TocopillaAntofagasta, Chile
    972.3×
  147. 147Saint-Jean-sur-RichelieuQuebec, Canada
    972.3×
  148. 149RockfordIllinois, United States
    972.2×
  149. 150DushanbeDushanbe, Tajikistan
    962.2×
  150. 150DhuleMaharashtra, India
    962.2×
  151. 150CallaoCallao, Peru
    962.2×
  152. 150BarbilOdisha, India
    962.2×
  153. 154BaripādaOdisha, India
    962.2×
  154. 154KeeneNew Hampshire, United States
    962.2×
  155. 156RourkelaOdisha, India
    962.2×
  156. 156DurgapurWest Bengal, India
    962.2×
  157. 156WyomingMichigan, United States
    962.2×
  158. 159NagaonAssam, India
    962.2×
  159. 159JenisonMichigan, United States
    962.2×
  160. 159MarquetteMichigan, United States
    962.2×
  161. 162UticaNew York, United States
    952.2×
  162. 162Rivière-des-Prairies–Pointe-aux-TremblesQuebec, Canada
    952.2×
  163. 164CauquenesMaule Region, Chile
    952.2×
  164. 165AnkleshwarGujarat, India
    952.2×
  165. 165ChigasakiKanagawa, Japan
    952.2×
  166. 167RochesterMinnesota, United States
    952.2×
  167. 168LewistonMaine, United States
    942.1×
  168. 169FukuroiShizuoka, Japan
    942.1×
  169. 169GreenfieldMassachusetts, United States
    942.1×
  170. 171DerryNew Hampshire, United States
    942.1×
  171. 172Faisalabadlow-cost sensorsPunjab, Pakistan
    932.1×
  172. 173GotembaShizuoka, Japan
    932.1×
  173. 174KalamazooMichigan, United States
    932.1×
  174. 174BurnsvilleMinnesota, United States
    932.1×
  175. 176KannurKerala, India
    932.1×
  176. 176PortlandMaine, United States
    932.1×
  177. 178BhiwandiMaharashtra, India
    932.1×
  178. 178Shaker HeightsOhio, United States
    932.1×
  179. 180PāliRajasthan, India
    922.1×
  180. 180OdawaraKanagawa, Japan
    922.1×
  181. 182AugustaMaine, United States
    922.1×
  182. 183ConcónValparaiso, Chile
    922.1×
  183. 183Franklin ParkIllinois, United States
    922.1×
  184. 185WaterburyConnecticut, United States
    922.1×
  185. 186KosaiShizuoka, Japan
    922.1×
  186. 187VapiGujarat, India
    912.1×
  187. 188BadlapurMaharashtra, India
    912.0×
  188. 188BelpaharOdisha, India
    912.0×
  189. 190La SerenaCoquimbo Region, Chile
    912.0×
  190. 190DanburyConnecticut, United States
    912.0×
  191. 190PithampurMadhya Pradesh, India
    912.0×
  192. 193QuthbullapurTelangana, India
    912.0×
  193. 194ShimodaShizuoka, Japan
    902.0×
  194. 195FrederictonNew Brunswick, Canada
    902.0×
  195. 196Sialkotlow-cost sensorsPunjab, Pakistan
    902.0×
  196. 196AtamiShizuoka, Japan
    902.0×
  197. 196Accralow-cost sensorsGreater Accra, Ghana
    902.0×
  198. 196NoidaUttar Pradesh, India
    902.0×
  199. 200SpringfieldMassachusetts, United States
    902.0×

Top 200 of 2,545 shown.

Good0–50
Moderate51–100
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

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SmogRank, most polluted cities, PM2.5, August 4, 2025, smogrank.com/history/2025-08-04 (accessed 2 Oct 2026).

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