SmogRank / History / July 31, 2025

Most polluted cities on July 31, 2025

2,586 cities ranked by their average PM2.5 over the day; the worst was Nagapattinam, India, at 205.0 µg/m³. Each city's own local calendar day.

Bad-air episodes during July 31, 2025. All episodes.

← Nagapattinam 205.0 µg/m³ 200 µg/m³15 WHO 24-hour guideline
Every city ranked for July 31, 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. 1NagapattinamTamil Nadu, India
    28013.7×
  2. 2Oconomowoclow-cost sensorsWisconsin, United States
    1907.4×
  3. 3SuperiorWisconsin, United States
    1846.8×
  4. 4MankatoMinnesota, United States
    1806.5×
  5. 5CoyhaiqueAysén, Chile
    1796.4×
  6. 6MilwaukeeWisconsin, United States
    1766.1×
  7. 7AppletonWisconsin, United States
    1735.8×
  8. 8Eau ClaireWisconsin, United States
    1735.8×
  9. 9WaukeshaWisconsin, United States
    1725.7×
  10. 10Green BayWisconsin, United States
    1725.7×
  11. 11DuluthMinnesota, United States
    1725.7×
  12. 12MarquetteMichigan, United States
    1715.6×
  13. 13South MilwaukeeWisconsin, United States
    1705.5×
  14. 14MadisonWisconsin, United States
    1705.5×
  15. 15RockfordIllinois, United States
    1685.3×
  16. 16ZionIllinois, United States
    1665.2×
  17. 17Franklin ParkIllinois, United States
    1665.1×
  18. 18RochesterMinnesota, United States
    1665.1×
  19. 19MolineIllinois, United States
    1655.1×
  20. 20Des PlainesIllinois, United States
    1655.1×
  21. 21CaryIllinois, United States
    1655.0×
  22. 22Fort DodgeIowa, United States
    1655.0×
  23. 23KigaliKigali, Rwanda
    1645.0×
  24. 24ClintonIowa, United States
    1644.9×
  25. 25ElginIllinois, United States
    1644.9×
  26. 26Grand RapidsMichigan, United States
    1634.9×
  27. 26BurnsvilleMinnesota, United States
    1634.9×
  28. 28ChāpraBihar, India
    1634.8×
  29. 29Elmwood ParkIllinois, United States
    1634.8×
  30. 30MinneapolisMinnesota, United States
    1624.7×
  31. 31BlaineMinnesota, United States
    1614.7×
  32. 32ChicagoIllinois, United States
    1614.6×
  33. 33ShakopeeMinnesota, United States
    1604.6×
  34. 34BridgeviewIllinois, United States
    1604.5×
  35. 35West FargoNorth Dakota, United States
    1594.5×
  36. 36JenisonMichigan, United States
    1594.5×
  37. 37Cedar RapidsIowa, United States
    1594.4×
  38. 38BrookfieldIllinois, United States
    1594.4×
  39. 39Apple ValleyMinnesota, United States
    1584.4×
  40. 40Saint PaulMinnesota, United States
    1584.3×
  41. 41Iowa CityIowa, United States
    1584.3×
  42. 42DoltonIllinois, United States
    1584.3×
  43. 43DavenportIowa, United States
    1574.3×
  44. 44AuroraIllinois, United States
    1574.2×
  45. 45OotyTamil Nadu, India
    1564.2×
  46. 46NapervilleIllinois, United States
    1564.2×
  47. 47UnderaGujarat, India
    1564.2×
  48. 48KalamazooMichigan, United States
    1554.1×
  49. 48Saint MichaelMinnesota, United States
    1554.1×
  50. 50NorthbrookIllinois, United States
    1554.0×
  51. 51JolietIllinois, United States
    1544.0×
  52. 51HammondIndiana, United States
    1544.0×
  53. 53LansingMichigan, United States
    1544.0×
  54. 54Faisalabadlow-cost sensorsPunjab, Pakistan
    1544.0×
  55. 55East ChicagoIndiana, United States
    1544.0×
  56. 56Dubailow-cost sensorsDubai, United Arab Emirates
    1533.9×
  57. 57Sri GanganagarRajasthan, India
    1533.9×
  58. 58PeoriaIllinois, United States
    1523.8×
  59. 58Saint CloudMinnesota, United States
    1523.8×
  60. 60Michigan CityIndiana, United States
    1523.8×
  61. 61Oak LawnIllinois, United States
    1523.8×
  62. 62Calumet CityIllinois, United States
    1513.7×
  63. 63NacimientoBiobio, Chile
    1513.7×
  64. 64PāliRajasthan, India
    1513.7×
  65. 65HollandMichigan, United States
    1503.7×
  66. 66WyomingMichigan, United States
    1483.6×
  67. 67WindsorOntario, Canada
    1483.6×
  68. 68RengoO'Higgins Region, Chile
    1483.6×
  69. 69SouthfieldMichigan, United States
    1443.5×
  70. 70Shakaskraallow-cost sensorsKwaZulu-Natal, South Africa
    1403.4×
  71. 71SarniaOntario, Canada
    1393.4×
  72. 72Bay CityMichigan, United States
    1373.4×
  73. 73MuscatineIowa, United States
    1373.3×
  74. 74YpsilantiMichigan, United States
    1353.3×
  75. 75BloomingtonIllinois, United States
    1343.2×
  76. 76Port HuronMichigan, United States
    1333.2×
  77. 77AnkenyIowa, United States
    1333.2×
  78. 77Des MoinesIowa, United States
    1333.2×
  79. 79DetroitMichigan, United States
    1313.2×
  80. 79MiltonOntario, Canada
    1313.2×
  81. 81DearbornMichigan, United States
    1303.1×
  82. 82Prince AlbertSaskatchewan, Canada
    1293.1×
  83. 83NewmarketOntario, Canada
    1293.1×
  84. 84OakvilleOntario, Canada
    1293.1×
  85. 85VapiGujarat, India
    1273.1×
  86. 86ElkhartIndiana, United States
    1273.1×
  87. 86PortageIndiana, United States
    1273.1×
  88. 86TorontoOntario, Canada
    1273.1×
  89. 89GaryIndiana, United States
    1273.1×
  90. 90ReginaSaskatchewan, Canada
    1253.0×
  91. 91EastpointeMichigan, United States
    1253.0×
  92. 92Lincoln ParkMichigan, United States
    1253.0×
  93. 93LondonOntario, Canada
    1243.0×
  94. 94South BendIndiana, United States
    1243.0×
  95. 95BramptonOntario, Canada
    1233.0×
  96. 96TaylorMichigan, United States
    1202.9×
  97. 96ChathamOntario, Canada
    1202.9×
  98. 98MississaugaOntario, Canada
    1192.9×
  99. 99KitchenerOntario, Canada
    1192.8×
  100. 100Multanlow-cost sensorsPunjab, Pakistan
    1182.8×
  101. 101St. ThomasOntario, Canada
    1172.8×
  102. 102GuelphOntario, Canada
    1162.8×
  103. 103BrantfordOntario, Canada
    1152.8×
  104. 104DushanbeDushanbe, Tajikistan
    1152.7×
  105. 105SaskatoonSaskatchewan, Canada
    1152.7×
  106. 106BrookingsSouth Dakota, United States
    1142.7×
  107. 106HamiltonOntario, Canada
    1142.7×
  108. 108RasapūdipalemAndhra Pradesh, India
    1142.7×
  109. 109Sioux FallsSouth Dakota, United States
    1132.7×
  110. 110BarrieOntario, Canada
    1132.7×
  111. 111AberdeenSouth Dakota, United States
    1122.7×
  112. 112WaterdownOntario, Canada
    1112.6×
  113. 113RedfordMichigan, United States
    1102.6×
  114. 114BuffaloNew York, United States
    1102.6×
  115. 115Ann Arborlow-cost sensorsMichigan, United States
    1092.6×
  116. 116MandideepMadhya Pradesh, India
    1082.6×
  117. 117WatertownSouth Dakota, United States
    1072.5×
  118. 118DhuleMaharashtra, India
    1072.5×
  119. 118AhmedabadGujarat, India
    1072.5×
  120. 120ToledoOhio, United States
    1052.5×
  121. 121TonkRajasthan, India
    1052.5×
  122. 122VijayawadaAndhra Pradesh, India
    1042.5×
  123. 123SpringfieldIllinois, United States
    1032.4×
  124. 124UdaipurRajasthan, India
    1032.4×
  125. 124AnantapurAndhra Pradesh, India
    1032.4×
  126. 124PeterboroughOntario, Canada
    1032.4×
  127. 124PithampurMadhya Pradesh, India
    1032.4×
  128. 128Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    1012.4×
  129. 129BānswāraRajasthan, India
    1002.4×
  130. 130HualpénBiobio, Chile
    992.3×
  131. 131AllistonOntario, Canada
    992.3×
  132. 132NandedMaharashtra, India
    982.3×
  133. 132FīrozābādUttar Pradesh, India
    982.3×
  134. 132RancaguaO'Higgins Region, Chile
    982.3×
  135. 135LudhianaPunjab, India
    982.3×
  136. 136Lexingtonlow-cost sensorsMassachusetts, United States
    972.3×
  137. 137KadapaAndhra Pradesh, India
    972.2×
  138. 138QuthbullapurTelangana, India
    962.2×
  139. 139LoniUttar Pradesh, India
    962.2×
  140. 140BadlapurMaharashtra, India
    962.2×
  141. 140SyracuseNew York, United States
    962.2×
  142. 142ThrissurKerala, India
    952.2×
  143. 143NagaonAssam, India
    952.2×
  144. 143HājīpurBihar, India
    952.2×
  145. 145Puerto AysénAysén, Chile
    952.2×
  146. 146Gujranwalalow-cost sensorsPunjab, Pakistan
    942.2×
  147. 147JaipurRajasthan, India
    942.2×
  148. 147BellevilleOntario, Canada
    942.2×
  149. 149Sault Ste. MarieOntario, Canada
    942.1×
  150. 150EriePennsylvania, United States
    942.1×
  151. 151Lahorelow-cost sensorsPunjab, Pakistan
    942.1×
  152. 151BhelaiChhattisgarh, India
    942.1×
  153. 151RochesterNew York, United States
    942.1×
  154. 151ByasanagarOdisha, India
    942.1×
  155. 151NandriRajasthan, India
    942.1×
  156. 156KannurKerala, India
    932.1×
  157. 156Dera Colliery TownshipOdisha, India
    932.1×
  158. 158ManamaManama, Bahrain
    932.1×
  159. 159AlangadKerala, India
    932.1×
  160. 160RājsamandRajasthan, India
    922.1×
  161. 161Hyderabadlow-cost sensorsSindh, Pakistan
    922.1×
  162. 162DūngarpurRajasthan, India
    922.1×
  163. 163BaripādaOdisha, India
    912.0×
  164. 163CuricóMaule Region, Chile
    912.0×
  165. 165NalbāriAssam, India
    912.0×
  166. 165ChittorgarhRajasthan, India
    912.0×
  167. 165BaddiHimachal Pradesh, India
    912.0×
  168. 168SaugorMadhya Pradesh, India
    902.0×
  169. 169DecaturIllinois, United States
    902.0×
  170. 169Fort WayneIndiana, United States
    902.0×
  171. 171KalyānMaharashtra, India
    902.0×
  172. 172St. CatharinesOntario, Canada
    902.0×
  173. 173AmritsarPunjab, India
    902.0×
  174. 174Columbialow-cost sensorsMissouri, United States
    892.0×
  175. 175GandhinagarGujarat, India
    892.0×
  176. 176Addis AbabaAddis Ababa, Ethiopia
    892.0×
  177. 176Wadgaon KolhatiMaharashtra, India
    892.0×
  178. 178San CarlosÑuble, Chile
    881.9×
  179. 179SantiagoSantiago Metropolitan, Chile
    881.9×
  180. 179OsornoLos Lagos Region, Chile
    881.9×
  181. 181MahādMaharashtra, India
    881.9×
  182. 181Ganghwa-gunIncheon, South Korea
    881.9×
  183. 183ChampaignIllinois, United States
    881.9×
  184. 184MalegaonMaharashtra, India
    881.9×
  185. 184Puente AltoSantiago Metropolitan, Chile
    881.9×
  186. 186ClevelandOhio, United States
    871.9×
  187. 187JodaOdisha, India
    871.9×
  188. 188JalorRajasthan, India
    871.9×
  189. 189CopiapóAtacama, Chile
    861.9×
  190. 190PainesvilleOhio, United States
    861.9×
  191. 191Karachilow-cost sensorsSindh, Pakistan
    861.8×
  192. 192RourkelaOdisha, India
    851.8×
  193. 192BegusaraiBihar, India
    851.8×
  194. 194Swift CurrentSaskatchewan, Canada
    851.8×
  195. 195Temalow-cost sensorsGreater Accra, Ghana
    841.8×
  196. 196Bahawalpurlow-cost sensorsPunjab, Pakistan
    841.8×
  197. 196GhāziābādUttar Pradesh, India
    841.8×
  198. 196BhiwandiMaharashtra, India
    841.8×
  199. 199SirohiRajasthan, India
    841.8×
  200. 200DewasMadhya Pradesh, India
    831.8×

Top 200 of 2,586 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

Use this board

SmogRank, most polluted cities, PM2.5, July 31, 2025, smogrank.com/history/2025-07-31 (accessed 2 Oct 2026).

Download top 10 (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms.