SmogRank / History / April 4, 2023

Most polluted cities on April 4, 2023

1,514 cities ranked by their average PM2.5 over the day; the worst was Mae Sai, Thailand, at 198.0 µg/m³. Each city's own local calendar day.

← Mae Sai 198.0 µg/m³ 150 µg/m³15 WHO 24-hour guideline
Every city ranked for April 4, 2023, 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. 1Mae SaiChiang Rai, Thailand
    27313.2×
  2. 2ReykjavíkCapital Region, Iceland
    26212.5×
  3. 3Ban HouakhouaBokeo, Laos
    24111.1×
  4. 4Tha BoNong Khai, Thailand
    2058.7×
  5. 5Chiang RaiChiang Rai, Thailand
    1947.8×
  6. 6PhayaoPhayao, Thailand
    1917.5×
  7. 7N'DjamenaN’Djaména, Chad
    1877.1×
  8. 8BamakoBamako, Mali
    1836.7×
  9. 9AlexandriaAlexandria, Egypt
    1826.7×
  10. 9ShenyangLiaoning, China
    1826.7×
  11. 11NanNan, Thailand
    1826.6×
  12. 12Chiang MaiChiang Mai, Thailand
    1786.3×
  13. 13LoeiLoei, Thailand
    1725.7×
  14. 14LampangLampang, Thailand
    1695.4×
  15. 15Dhakalow-cost sensorsDhaka Division, Bangladesh
    1685.3×
  16. 16OsornoLos Lagos Region, Chile
    1675.2×
  17. 17PhraePhrae, Thailand
    1665.1×
  18. 18Ciudad Benito JuárezNuevo León, Mexico
    1624.8×
  19. 19LamphunLamphun, Thailand
    1614.6×
  20. 20CholulaPuebla, Mexico
    1604.5×
  21. 21Puerto MonttLos Lagos Region, Chile
    1594.4×
  22. 22Kamphaeng PhetKamphaeng Phet, Thailand
    1574.3×
  23. 23TlaquepaqueJalisco, Mexico
    1564.2×
  24. 24Lahorelow-cost sensorsPunjab, Pakistan
    1544.0×
  25. 25Nakhon SawanNakhon Sawan, Thailand
    1523.8×
  26. 26PhichitPhichit, Thailand
    1513.7×
  27. 27Sing BuriSing Buri, Thailand
    1503.7×
  28. 28UttaraditUttaradit, Thailand
    1473.6×
  29. 29Suphan BuriSuphan Buri, Thailand
    1443.5×
  30. 30Lop BuriLopburi, Thailand
    1433.5×
  31. 31Udon ThaniUdon Thani, Thailand
    1393.4×
  32. 31Nong Bua LamphuNong Bua Lamphu, Thailand
    1393.4×
  33. 33Puerto VarasLos Lagos Region, Chile
    1383.4×
  34. 34Ubon RatchathaniUbon Ratchathani, Thailand
    1373.4×
  35. 35Mae SotTak, Thailand
    1373.3×
  36. 36San Mateo AtencoMéxico, Mexico
    1343.3×
  37. 37RatchaburiRatchaburi, Thailand
    1333.2×
  38. 38HanoiHanoi, Vietnam
    1313.2×
  39. 39KalasinKalasin, Thailand
    1293.1×
  40. 40Sakon NakhonSakon Nakhon, Thailand
    1293.1×
  41. 40PakxanBolikhamsai, Laos
    1293.1×
  42. 42Phra Nakhon Si AyutthayaPhra Nakhon Si Ayutthaya, Thailand
    1273.1×
  43. 43MexicaliBaja California, Mexico
    1273.1×
  44. 44Bang NaBangkok, Thailand
    1263.0×
  45. 45Ciudad JuárezChihuahua, Mexico
    1253.0×
  46. 46Nong KhaemBangkok, Thailand
    1253.0×
  47. 47Ban Samae DamBangkok, Thailand
    1243.0×
  48. 48Khon KaenKhon Kaen, Thailand
    1233.0×
  49. 49KanchanaburiKanchanaburi, Thailand
    1222.9×
  50. 50Nakhon RatchasimaNakhon Ratchasima, Thailand
    1212.9×
  51. 51Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    1192.9×
  52. 52ChaiyaphumChaiyaphum, Thailand
    1192.9×
  53. 53MonterreyNuevo León, Mexico
    1182.8×
  54. 54PhetchabunPhetchabun, Thailand
    1172.8×
  55. 55SukhothaiSukhothai, Thailand
    1172.8×
  56. 56Roi EtRoi Et, Thailand
    1162.8×
  57. 57La UniónLos Ríos Region, Chile
    1152.8×
  58. 57Khlong Sam WaBangkok, Thailand
    1152.8×
  59. 59Hua HinPrachuap Khiri Khan, Thailand
    1152.7×
  60. 60BangkokBangkok, Thailand
    1142.7×
  61. 61XonacatlánMéxico, Mexico
    1112.6×
  62. 62Samut PrakanSamut Prakan, Thailand
    1112.6×
  63. 62TolucaMéxico, Mexico
    1112.6×
  64. 64CelayaGuanajuato, Mexico
    1112.6×
  65. 65Ciudad ApodacaNuevo León, Mexico
    1112.6×
  66. 66Nakhon PathomNakhon Pathom, Thailand
    1102.6×
  67. 67Ga-RankuwaNorth West, South Africa
    1092.6×
  68. 68BaghdadBaghdad, Iraq
    1082.6×
  69. 69Santa CatarinaNuevo León, Mexico
    1072.5×
  70. 70HyderabadTelangana, India
    1062.5×
  71. 70GarcíaNuevo León, Mexico
    1062.5×
  72. 72Nong ChokBangkok, Thailand
    1052.5×
  73. 72Lak SiBangkok, Thailand
    1052.5×
  74. 74Kathmandulow-cost sensorsBagmati Province, Nepal
    1052.5×
  75. 75Mueang NonthaburiNonthaburi, Thailand
    1042.5×
  76. 76Bang KapiBangkok, Thailand
    1042.5×
  77. 77Si Maha PhotPrachin Buri, Thailand
    1042.4×
  78. 77Sai MaiBangkok, Thailand
    1042.4×
  79. 79TakTak, Thailand
    1032.4×
  80. 79Saphan SungBangkok, Thailand
    1032.4×
  81. 81BloemfonteinFree State, South Africa
    1032.4×
  82. 82Si Sa KetSi Sa Ket, Thailand
    1032.4×
  83. 83DelhiDelhi, India
    1022.4×
  84. 83Phra PradaengSamut Prakan, Thailand
    1022.4×
  85. 85Bueng KumBangkok, Thailand
    1022.4×
  86. 86Samut SakhonSamut Sakhon, Thailand
    1012.4×
  87. 86Khan Na YaoBangkok, Thailand
    1012.4×
  88. 88Ciudad NezahualcoyotlMéxico, Mexico
    1002.4×
  89. 89SaraburiSaraburi, Thailand
    1002.4×
  90. 90Khlong LuangPathum Thani, Thailand
    1002.3×
  91. 91RabinalBaja Verapaz, Guatemala
    992.3×
  92. 91Guatemala CityGuatemala, Guatemala
    992.3×
  93. 93ConakryConakry, Guinea
    982.3×
  94. 94Lagoslow-cost sensorsLagos, Nigeria
    972.3×
  95. 95Ban Khlong PrawetBangkok, Thailand
    972.2×
  96. 96ValdiviaLos Ríos Region, Chile
    962.2×
  97. 97San Francisco TlalcilalcalpanMéxico, Mexico
    962.2×
  98. 98Buri RamBuriram, Thailand
    952.2×
  99. 99LubbockTexas, United States
    952.2×
  100. 100Abujalow-cost sensorsFCT, Nigeria
    942.1×
  101. 101Ciudad General EscobedoNuevo León, Mexico
    932.1×
  102. 101Lat KrabangBangkok, Thailand
    932.1×
  103. 103VeracruzVeracruz, Mexico
    912.0×
  104. 104HualquiBiobio, Chile
    912.0×
  105. 105Cadereyta JiménezNuevo León, Mexico
    902.0×
  106. 106Laem ChabangChon Buri, Thailand
    902.0×
  107. 106HualpénBiobio, Chile
    902.0×
  108. 108Ban ChangRayong, Thailand
    902.0×
  109. 108AmarilloTexas, United States
    902.0×
  110. 110ValjevoCentral Serbia, Serbia
    892.0×
  111. 111Puerto AysénAysén, Chile
    892.0×
  112. 112SantiagoSantiago Metropolitan, Chile
    881.9×
  113. 112ZapopanJalisco, Mexico
    881.9×
  114. 114CuernavacaMorelos, Mexico
    881.9×
  115. 115Islamabadlow-cost sensorsIslamabad, Pakistan
    881.9×
  116. 115PueblaPuebla, Mexico
    881.9×
  117. 117Santiago de QuerétaroQuerétaro, Mexico
    871.9×
  118. 118BakuBaki, Azerbaijan
    861.9×
  119. 119Bang Bo DistrictSamut Prakan, Thailand
    861.9×
  120. 119Accralow-cost sensorsGreater Accra, Ghana
    861.9×
  121. 121NacimientoBiobio, Chile
    861.9×
  122. 122Kampalalow-cost sensorsCentral Region, Uganda
    861.9×
  123. 122Almatylow-cost sensorsAlmaty, Kazakhstan
    861.9×
  124. 124Mexico CityMexico City, Mexico
    851.8×
  125. 124Viña del MarValparaiso, Chile
    851.8×
  126. 126CuranilahueBiobio, Chile
    851.8×
  127. 127RayongRayong, Thailand
    851.8×
  128. 127TalaganteSantiago Metropolitan, Chile
    851.8×
  129. 127QuillotaValparaiso, Chile
    851.8×
  130. 130GuangzhouGuangdong, China
    851.8×
  131. 130CayenneGuyane, French Guiana
    851.8×
  132. 132Novi PazarCentral Serbia, Serbia
    851.8×
  133. 132CoyhaiqueAysén, Chile
    851.8×
  134. 134CoronelBiobio, Chile
    841.8×
  135. 135Tepeji del Río de OcampoHidalgo, Mexico
    841.8×
  136. 135QuinteroValparaiso, Chile
    841.8×
  137. 137KhartoumKhartoum, Sudan
    841.8×
  138. 137YangonYangon, Myanmar
    841.8×
  139. 139AricaArica y Parinacota Region, Chile
    831.8×
  140. 140TemucoAraucania, Chile
    821.7×
  141. 141Addis AbabaAddis Ababa, Ethiopia
    821.7×
  142. 142Ban Talat BuengChon Buri, Thailand
    821.7×
  143. 142LinaresMaule Region, Chile
    821.7×
  144. 144ConcónValparaiso, Chile
    811.7×
  145. 144San Luis de la PazGuanajuato, Mexico
    811.7×
  146. 146CuricóMaule Region, Chile
    811.7×
  147. 147RancaguaO'Higgins Region, Chile
    811.7×
  148. 148PristinaPristina, Kosovo
    801.7×
  149. 149SocorroTexas, United States
    801.6×
  150. 150Puente AltoSantiago Metropolitan, Chile
    801.6×
  151. 151LaredoTexas, United States
    791.6×
  152. 152ToméBiobio, Chile
    791.6×
  153. 153Naucalpan de JuárezMéxico, Mexico
    791.6×
  154. 154San CarlosÑuble, Chile
    781.6×
  155. 155Surat ThaniSurat Thani, Thailand
    781.6×
  156. 155Pachuca de SotoHidalgo, Mexico
    781.6×
  157. 155SalamancaGuanajuato, Mexico
    781.6×
  158. 155EdinburgTexas, United States
    781.6×
  159. 159TalcaMaule Region, Chile
    781.6×
  160. 160ChillánÑuble, Chile
    771.6×
  161. 161GuadalajaraJalisco, Mexico
    771.5×
  162. 162CauquenesMaule Region, Chile
    761.5×
  163. 163San Miguel de AllendeGuanajuato, Mexico
    751.5×
  164. 164AustinTexas, United States
    751.5×
  165. 165La SerenaCoquimbo Region, Chile
    751.5×
  166. 166TalcahuanoBiobio, Chile
    741.4×
  167. 167YalaYala, Thailand
    741.4×
  168. 167Rio ClaroSão Paulo, Brazil
    741.4×
  169. 169León de los AldamaGuanajuato, Mexico
    741.4×
  170. 169San AntonioTexas, United States
    741.4×
  171. 171TulsaOklahoma, United States
    741.4×
  172. 172Jastrzębie ZdrójSilesia, Poland
    731.4×
  173. 173LimeiraSão Paulo, Brazil
    731.4×
  174. 174Wan ChaiWan Chai, Hong Kong
    731.4×
  175. 174San Luis PotosíSan Luis Potosí, Mexico
    731.4×
  176. 176ChanthaburiChanthaburi, Thailand
    721.4×
  177. 176McAlesterOklahoma, United States
    721.4×
  178. 178Şabāḩ as SālimMubārak al Kabīr, Kuwait
    721.4×
  179. 178SalorTashkent Region, Uzbekistan
    721.4×
  180. 178Hat YaiSongkhla, Thailand
    721.4×
  181. 178BeijingBeijing, China
    721.4×
  182. 178CampinasSão Paulo, Brazil
    721.4×
  183. 178AntofagastaAntofagasta, Chile
    721.4×
  184. 184RengoO'Higgins Region, Chile
    721.4×
  185. 185San Andrés TuxtlaVeracruz, Mexico
    721.4×
  186. 186ChiguayanteBiobio, Chile
    721.3×
  187. 187Corpus ChristiTexas, United States
    711.3×
  188. 188Bishkeklow-cost sensorsBishkek, Kyrgyzstan
    711.3×
  189. 188CoquimboCoquimbo Region, Chile
    711.3×
  190. 188San Pedro de la PazBiobio, Chile
    711.3×
  191. 191MooreOklahoma, United States
    711.3×
  192. 192RacibórzSilesia, Poland
    711.3×
  193. 192BeltonTexas, United States
    711.3×
  194. 192HobbsNew Mexico, United States
    711.3×
  195. 195JenksOklahoma, United States
    711.3×
  196. 195CorsicanaTexas, United States
    711.3×
  197. 195HoustonTexas, United States
    711.3×
  198. 198GuanajuatoGuanajuato, Mexico
    701.3×
  199. 199SpringfieldMissouri, United States
    701.3×
  200. 200Fort WorthTexas, United States
    701.3×

Top 200 of 1,514 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, April 4, 2023, smogrank.com/history/2023-04-04 (accessed 2 Oct 2026).

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