SmogRank / History / April 20, 2023

Most polluted cities on April 20, 2023

1,495 cities ranked by their average PM2.5 over the day; the worst was Mexicali, Mexico, at 452.7 µg/m³. Each city's own local calendar day.

Bad-air episodes during April 20, 2023. All episodes.

← Mexicali 452.7 µg/m³ 400 µg/m³15 WHO 24-hour guideline
Every city ranked for April 20, 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. 1MexicaliBaja California, Mexico
    500+30.2×
  2. 2Piedras NegrasCoahuila, Mexico
    500+23.5×
  3. 3ZapopanJalisco, Mexico
    28914.3×
  4. 4Ban HouakhouaBokeo, Laos
    2209.7×
  5. 5BeijingBeijing, China
    2139.2×
  6. 6Mae SaiChiang Rai, Thailand
    2068.7×
  7. 7San Mateo AtencoMéxico, Mexico
    1927.6×
  8. 8NanNan, Thailand
    1836.7×
  9. 9AguascalientesAguascalientes, Mexico
    1786.3×
  10. 10PhayaoPhayao, Thailand
    1786.3×
  11. 11LampangLampang, Thailand
    1786.2×
  12. 12Kathmandulow-cost sensorsBagmati Province, Nepal
    1786.2×
  13. 13Chiang MaiChiang Mai, Thailand
    1735.8×
  14. 14BamakoBamako, Mali
    1695.4×
  15. 15UttaraditUttaradit, Thailand
    1685.3×
  16. 16PhraePhrae, Thailand
    1644.9×
  17. 17Dhakalow-cost sensorsDhaka Division, Bangladesh
    1634.9×
  18. 18Kamphaeng PhetKamphaeng Phet, Thailand
    1624.8×
  19. 19Bang Khun ThianBangkok, Thailand
    1624.7×
  20. 20LoeiLoei, Thailand
    1624.7×
  21. 21LamphunLamphun, Thailand
    1614.7×
  22. 22TlaquepaqueJalisco, Mexico
    1614.6×
  23. 23PhetchabunPhetchabun, Thailand
    1614.6×
  24. 24PhichitPhichit, Thailand
    1614.6×
  25. 25HyderabadTelangana, India
    1604.6×
  26. 26PakxanBolikhamsai, Laos
    1604.5×
  27. 27BrakpanGauteng, South Africa
    1594.5×
  28. 28Udon ThaniUdon Thani, Thailand
    1574.2×
  29. 28Chai NatChai Nat, Thailand
    1574.2×
  30. 30Nakhon SawanNakhon Sawan, Thailand
    1564.1×
  31. 30Lop BuriLopburi, Thailand
    1564.1×
  32. 32Sing BuriSing Buri, Thailand
    1554.1×
  33. 33CuranilahueBiobio, Chile
    1554.1×
  34. 34SukhothaiSukhothai, Thailand
    1544.0×
  35. 35HanoiHanoi, Vietnam
    1543.9×
  36. 35Nong Bua LamphuNong Bua Lamphu, Thailand
    1543.9×
  37. 37YangonYangon, Myanmar
    1533.9×
  38. 38Suphan BuriSuphan Buri, Thailand
    1523.8×
  39. 39Bang NaBangkok, Thailand
    1523.8×
  40. 40BaghdadBaghdad, Iraq
    1523.8×
  41. 41TakTak, Thailand
    1483.6×
  42. 42ChaiyaphumChaiyaphum, Thailand
    1483.6×
  43. 43RatchaburiRatchaburi, Thailand
    1463.6×
  44. 44Ubon RatchathaniUbon Ratchathani, Thailand
    1443.5×
  45. 45Nong KhaemBangkok, Thailand
    1433.5×
  46. 45Ban ChangRayong, Thailand
    1433.5×
  47. 47Khon KaenKhon Kaen, Thailand
    1433.5×
  48. 48Khlong Sam WaBangkok, Thailand
    1423.5×
  49. 49KalasinKalasin, Thailand
    1423.5×
  50. 50CholulaPuebla, Mexico
    1423.5×
  51. 51Hua HinPrachuap Khiri Khan, Thailand
    1373.3×
  52. 52Ban Samae DamBangkok, Thailand
    1373.3×
  53. 53Khan Na YaoBangkok, Thailand
    1373.3×
  54. 54BloemfonteinFree State, South Africa
    1353.3×
  55. 54Samut PrakanSamut Prakan, Thailand
    1353.3×
  56. 56Phra Nakhon Si AyutthayaPhra Nakhon Si Ayutthaya, Thailand
    1353.3×
  57. 56Bueng KumBangkok, Thailand
    1353.3×
  58. 58Nakhon PathomNakhon Pathom, Thailand
    1343.3×
  59. 59GuangzhouGuangdong, China
    1333.2×
  60. 60Lak SiBangkok, Thailand
    1323.2×
  61. 61BangkokBangkok, Thailand
    1323.2×
  62. 62Nakhon RatchasimaNakhon Ratchasima, Thailand
    1303.1×
  63. 63Saphan SungBangkok, Thailand
    1293.1×
  64. 64ThembisaGauteng, South Africa
    1293.1×
  65. 65SaraburiSaraburi, Thailand
    1283.1×
  66. 65Bang KapiBangkok, Thailand
    1283.1×
  67. 65Lat KrabangBangkok, Thailand
    1283.1×
  68. 68Nong ChokBangkok, Thailand
    1273.1×
  69. 69Phra PradaengSamut Prakan, Thailand
    1263.0×
  70. 70Si Maha PhotPrachin Buri, Thailand
    1253.0×
  71. 71Sai MaiBangkok, Thailand
    1243.0×
  72. 72Mueang NonthaburiNonthaburi, Thailand
    1243.0×
  73. 73Khlong LuangPathum Thani, Thailand
    1243.0×
  74. 74Laem ChabangChon Buri, Thailand
    1233.0×
  75. 75Ban Khlong PrawetBangkok, Thailand
    1233.0×
  76. 76MukdahanMukdahan, Thailand
    1222.9×
  77. 77Samut SakhonSamut Sakhon, Thailand
    1222.9×
  78. 78Roi EtRoi Et, Thailand
    1212.9×
  79. 79RabinalBaja Verapaz, Guatemala
    1192.9×
  80. 79Guatemala CityGuatemala, Guatemala
    1192.9×
  81. 81Sakon NakhonSakon Nakhon, Thailand
    1192.9×
  82. 82Ban Talat BuengChon Buri, Thailand
    1182.8×
  83. 83LinaresMaule Region, Chile
    1172.8×
  84. 84JohannesburgGauteng, South Africa
    1162.8×
  85. 84CelayaGuanajuato, Mexico
    1162.8×
  86. 86Şabāḩ as SālimMubārak al Kabīr, Kuwait
    1142.7×
  87. 86DelhiDelhi, India
    1142.7×
  88. 88Novi PazarCentral Serbia, Serbia
    1142.7×
  89. 89Ciudad Benito JuárezNuevo León, Mexico
    1112.6×
  90. 90RayongRayong, Thailand
    1102.6×
  91. 90SantiagoSantiago Metropolitan, Chile
    1102.6×
  92. 92SasolburgFree State, South Africa
    1092.6×
  93. 92KanchanaburiKanchanaburi, Thailand
    1092.6×
  94. 94Jastrzębie ZdrójSilesia, Poland
    1042.4×
  95. 95TalaganteSantiago Metropolitan, Chile
    1032.4×
  96. 96PirotCentral Serbia, Serbia
    1032.4×
  97. 97CuricóMaule Region, Chile
    1022.4×
  98. 98Tepeji del Río de OcampoHidalgo, Mexico
    1012.4×
  99. 99JakartaJakarta, Indonesia
    1012.4×
  100. 100KigaliKigali, Rwanda
    1002.4×
  101. 100XonacatlánMéxico, Mexico
    1002.4×
  102. 102VereenigingGauteng, South Africa
    1002.3×
  103. 102Buri RamBuriram, Thailand
    1002.3×
  104. 102San CarlosÑuble, Chile
    1002.3×
  105. 102RancaguaO'Higgins Region, Chile
    1002.3×
  106. 106Si Sa KetSi Sa Ket, Thailand
    992.3×
  107. 106La SerenaCoquimbo Region, Chile
    992.3×
  108. 108PristinaPristina, Kosovo
    992.3×
  109. 109TolucaMéxico, Mexico
    972.3×
  110. 110ChillánÑuble, Chile
    972.3×
  111. 111TocopillaAntofagasta, Chile
    972.2×
  112. 112NacimientoBiobio, Chile
    962.2×
  113. 113HueytownAlabama, United States
    962.2×
  114. 114Surat ThaniSurat Thani, Thailand
    962.2×
  115. 115ChanthaburiChanthaburi, Thailand
    962.2×
  116. 116Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    952.2×
  117. 117TijuanaBaja California, Mexico
    942.2×
  118. 118VanderbijlparkGauteng, South Africa
    942.1×
  119. 119PhuketPhuket, Thailand
    942.1×
  120. 119Hat YaiSongkhla, Thailand
    942.1×
  121. 119Puerto VarasLos Lagos Region, Chile
    942.1×
  122. 122San Francisco TlalcilalcalpanMéxico, Mexico
    932.1×
  123. 123Ga-RankuwaNorth West, South Africa
    932.1×
  124. 124RacibórzSilesia, Poland
    932.1×
  125. 125HualquiBiobio, Chile
    922.1×
  126. 126LimaLima Province, Peru
    912.0×
  127. 127VisbyGotland, Sweden
    912.0×
  128. 127RengoO'Higgins Region, Chile
    912.0×
  129. 129SatunSatun, Thailand
    902.0×
  130. 129PueblaPuebla, Mexico
    902.0×
  131. 131TrangTrang, Thailand
    902.0×
  132. 132ValjevoCentral Serbia, Serbia
    902.0×
  133. 132HualpénBiobio, Chile
    902.0×
  134. 134Lahorelow-cost sensorsPunjab, Pakistan
    892.0×
  135. 135ĆuprijaCentral Serbia, Serbia
    892.0×
  136. 136Jelenia GóraLower Silesia, Poland
    892.0×
  137. 137TalcaMaule Region, Chile
    892.0×
  138. 138CoquimboCoquimbo Region, Chile
    881.9×
  139. 139GarcíaNuevo León, Mexico
    881.9×
  140. 140TalcahuanoBiobio, Chile
    871.9×
  141. 140CoronelBiobio, Chile
    871.9×
  142. 142Addis AbabaAddis Ababa, Ethiopia
    871.9×
  143. 142AranyaprathetSa Kaeo, Thailand
    871.9×
  144. 142Ciudad ApodacaNuevo León, Mexico
    871.9×
  145. 145Viña del MarValparaiso, Chile
    861.9×
  146. 146AshgabatAshgabat, Turkmenistan
    861.9×
  147. 146YalaYala, Thailand
    861.9×
  148. 146San Andrés TuxtlaVeracruz, Mexico
    861.9×
  149. 149AntofagastaAntofagasta, Chile
    851.8×
  150. 149Silao de la VictoriaGuanajuato, Mexico
    851.8×
  151. 149GuadalajaraJalisco, Mexico
    851.8×
  152. 152BakuBaki, Azerbaijan
    851.8×
  153. 152Nakhon Si ThammaratNakhon Si Thammarat, Thailand
    851.8×
  154. 152CoyhaiqueAysén, Chile
    851.8×
  155. 155LazarevacCentral Serbia, Serbia
    851.8×
  156. 155Kinshasalow-cost sensorsKinshasa, Democratic Republic of the Congo
    851.8×
  157. 155CuernavacaMorelos, Mexico
    851.8×
  158. 158QuillotaValparaiso, Chile
    851.8×
  159. 159QuinteroValparaiso, Chile
    841.8×
  160. 160ŁaskŁódź Voivodeship, Poland
    841.8×
  161. 161HavířovMoravian-Silesian Region, Czechia
    841.8×
  162. 161OdessaTexas, United States
    841.8×
  163. 163Naucalpan de JuárezMéxico, Mexico
    831.8×
  164. 164AnconaThe Marches, Italy
    821.7×
  165. 165Kampalalow-cost sensorsCentral Region, Uganda
    821.7×
  166. 166TurinPiedmont, Italy
    821.7×
  167. 166ToméBiobio, Chile
    821.7×
  168. 168VeracruzVeracruz, Mexico
    821.7×
  169. 168Santa Anita - Los FicusLima region, Peru
    821.7×
  170. 170TratTrat, Thailand
    811.7×
  171. 170Mexico CityMexico City, Mexico
    811.7×
  172. 172Santa CatarinaNuevo León, Mexico
    811.7×
  173. 173Czechowice-DziedziceSilesia, Poland
    811.7×
  174. 173Santiago de QuerétaroQuerétaro, Mexico
    811.7×
  175. 175Novi SadVojvodina, Serbia
    811.7×
  176. 175San Francisco De BorjaLima region, Peru
    811.7×
  177. 177KościanGreater Poland, Poland
    811.7×
  178. 178ShenyangLiaoning, China
    801.7×
  179. 178ConakryConakry, Guinea
    801.7×
  180. 178KłodzkoLower Silesia, Poland
    801.7×
  181. 181Bishkeklow-cost sensorsBishkek, Kyrgyzstan
    801.6×
  182. 181OstravaMoravian-Silesian Region, Czechia
    801.6×
  183. 181CalexicoCalifornia, United States
    801.6×
  184. 184MonterreyNuevo León, Mexico
    801.6×
  185. 185SalorTashkent Region, Uzbekistan
    801.6×
  186. 186TarnówLesser Poland, Poland
    791.6×
  187. 186AricaArica y Parinacota Region, Chile
    791.6×
  188. 188Bielsko-BialaSilesia, Poland
    791.6×
  189. 189LotaBiobio, Chile
    791.6×
  190. 190Puente AltoSantiago Metropolitan, Chile
    781.6×
  191. 191San Juan del RíoQuerétaro, Mexico
    781.6×
  192. 192NišCentral Serbia, Serbia
    781.6×
  193. 192MumbaiMaharashtra, India
    781.6×
  194. 192ConcónValparaiso, Chile
    781.6×
  195. 195ZemunCentral Serbia, Serbia
    771.5×
  196. 195NarathiwatNarathiwat, Thailand
    771.5×
  197. 195TlaxcalaTlaxcala, Mexico
    771.5×
  198. 195SalamancaGuanajuato, Mexico
    771.5×
  199. 199KrakówLesser Poland, Poland
    761.5×
  200. 200KhartoumKhartoum, Sudan
    761.5×

Top 200 of 1,495 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 20, 2023, smogrank.com/history/2023-04-20 (accessed 2 Oct 2026).

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