SmogRank / History / March 31, 2023

Most polluted cities on March 31, 2023

1,519 cities ranked by their average PM2.5 over the day; the worst was Mae Sai, Thailand, at 275.0 µg/m³. Each city's own local calendar day.

← Mae Sai 275.0 µg/m³ 200 µg/m³15 WHO 24-hour guideline
Every city ranked for March 31, 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
    40018.3×
  2. 2Chiang RaiChiang Rai, Thailand
    36217.1×
  3. 3N'DjamenaN’Djaména, Chad
    32815.9×
  4. 4Ban HouakhouaBokeo, Laos
    30415.1×
  5. 5Chiang MaiChiang Mai, Thailand
    22910.3×
  6. 6ReykjavíkCapital Region, Iceland
    2219.7×
  7. 7NanNan, Thailand
    2028.5×
  8. 8LampangLampang, Thailand
    1967.9×
  9. 9LamphunLamphun, Thailand
    1877.1×
  10. 10BaghdadBaghdad, Iraq
    1776.2×
  11. 11Kathmandulow-cost sensorsBagmati Province, Nepal
    1715.6×
  12. 12Ciudad Benito JuárezNuevo León, Mexico
    1705.5×
  13. 13TlaquepaqueJalisco, Mexico
    1695.4×
  14. 14KhartoumKhartoum, Sudan
    1695.4×
  15. 15LoeiLoei, Thailand
    1675.2×
  16. 16ShenyangLiaoning, China
    1665.1×
  17. 17PhraePhrae, Thailand
    1634.8×
  18. 18HanoiHanoi, Vietnam
    1624.8×
  19. 19Mae SotTak, Thailand
    1604.6×
  20. 20Dhakalow-cost sensorsDhaka Division, Bangladesh
    1574.3×
  21. 21OsornoLos Lagos Region, Chile
    1574.2×
  22. 22Tha BoNong Khai, Thailand
    1533.9×
  23. 23Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    1513.7×
  24. 24BeijingBeijing, China
    1493.7×
  25. 25BamakoBamako, Mali
    1493.7×
  26. 26SukhothaiSukhothai, Thailand
    1483.6×
  27. 27HyderabadTelangana, India
    1453.6×
  28. 28Kamphaeng PhetKamphaeng Phet, Thailand
    1443.5×
  29. 29CoyhaiqueAysén, Chile
    1423.5×
  30. 30UttaraditUttaradit, Thailand
    1413.5×
  31. 31Bang Khun ThianBangkok, Thailand
    1363.3×
  32. 32PhichitPhichit, Thailand
    1353.3×
  33. 33MukdahanMukdahan, Thailand
    1343.3×
  34. 34PhetchabunPhetchabun, Thailand
    1333.2×
  35. 35Ciudad ApodacaNuevo León, Mexico
    1313.2×
  36. 36Ubon RatchathaniUbon Ratchathani, Thailand
    1283.1×
  37. 37Abujalow-cost sensorsFCT, Nigeria
    1283.1×
  38. 38Puerto VarasLos Lagos Region, Chile
    1253.0×
  39. 39YangonYangon, Myanmar
    1192.9×
  40. 40HualquiBiobio, Chile
    1182.8×
  41. 41KanchanaburiKanchanaburi, Thailand
    1182.8×
  42. 42Udon ThaniUdon Thani, Thailand
    1172.8×
  43. 42GarcíaNuevo León, Mexico
    1172.8×
  44. 44RatchaburiRatchaburi, Thailand
    1162.8×
  45. 45Khon KaenKhon Kaen, Thailand
    1152.7×
  46. 46Şabāḩ as SālimMubārak al Kabīr, Kuwait
    1152.7×
  47. 47MonterreyNuevo León, Mexico
    1152.7×
  48. 48Puerto MonttLos Lagos Region, Chile
    1142.7×
  49. 49Santa CatarinaNuevo León, Mexico
    1142.7×
  50. 50PakxanBolikhamsai, Laos
    1132.7×
  51. 51Sakon NakhonSakon Nakhon, Thailand
    1122.7×
  52. 52San Mateo AtencoMéxico, Mexico
    1122.7×
  53. 53TakTak, Thailand
    1112.6×
  54. 54Nong Bua LamphuNong Bua Lamphu, Thailand
    1112.6×
  55. 55KalasinKalasin, Thailand
    1102.6×
  56. 56Ciudad JuárezChihuahua, Mexico
    1082.6×
  57. 57La OrotavaCanary Islands, Spain
    1052.5×
  58. 58Puerto AysénAysén, Chile
    1022.4×
  59. 59MexicaliBaja California, Mexico
    1012.4×
  60. 60CelayaGuanajuato, Mexico
    992.3×
  61. 61Sing BuriSing Buri, Thailand
    992.3×
  62. 62Roi EtRoi Et, Thailand
    982.3×
  63. 62Cadereyta JiménezNuevo León, Mexico
    982.3×
  64. 64Nakhon SawanNakhon Sawan, Thailand
    982.3×
  65. 65ChaiyaphumChaiyaphum, Thailand
    982.3×
  66. 66Ciudad NezahualcoyotlMéxico, Mexico
    982.3×
  67. 66QuinteroValparaiso, Chile
    982.3×
  68. 68AlexandriaAlexandria, Egypt
    972.3×
  69. 69ChisinauChișinău Municipality, Moldova
    972.3×
  70. 70XonacatlánMéxico, Mexico
    972.2×
  71. 70San Salvador TizatlalliMéxico, Mexico
    972.2×
  72. 72Nakhon RatchasimaNakhon Ratchasima, Thailand
    972.2×
  73. 73La UniónLos Ríos Region, Chile
    962.2×
  74. 74NacimientoBiobio, Chile
    962.2×
  75. 75TolucaMéxico, Mexico
    962.2×
  76. 76CuranilahueBiobio, Chile
    952.2×
  77. 77Si Sa KetSi Sa Ket, Thailand
    942.1×
  78. 77HualpénBiobio, Chile
    942.1×
  79. 79MinatitlánVeracruz, Mexico
    932.1×
  80. 80OviedoAsturias, Spain
    932.1×
  81. 81Lahorelow-cost sensorsPunjab, Pakistan
    922.1×
  82. 82Lop BuriLopburi, Thailand
    912.1×
  83. 83San Francisco TlalcilalcalpanMéxico, Mexico
    912.0×
  84. 84Suphan BuriSuphan Buri, Thailand
    902.0×
  85. 85TemucoAraucania, Chile
    892.0×
  86. 86SamaAsturias, Spain
    892.0×
  87. 87TalcahuanoBiobio, Chile
    881.9×
  88. 88TalaganteSantiago Metropolitan, Chile
    871.9×
  89. 89TocopillaAntofagasta, Chile
    861.9×
  90. 90San CarlosÑuble, Chile
    861.9×
  91. 91SantiagoSantiago Metropolitan, Chile
    851.8×
  92. 92ToméBiobio, Chile
    851.8×
  93. 92ConcónValparaiso, Chile
    851.8×
  94. 94Mexico CityMexico City, Mexico
    851.8×
  95. 95ChillánÑuble, Chile
    851.8×
  96. 96Los ÁngelesBiobio, Chile
    851.8×
  97. 97DelhiDelhi, India
    841.8×
  98. 97Bang NaBangkok, Thailand
    841.8×
  99. 99ValjevoCentral Serbia, Serbia
    841.8×
  100. 99Naucalpan de JuárezMéxico, Mexico
    841.8×
  101. 101RancaguaO'Higgins Region, Chile
    841.8×
  102. 102PristinaPristina, Kosovo
    841.8×
  103. 102QuillotaValparaiso, Chile
    841.8×
  104. 102Puente AltoSantiago Metropolitan, Chile
    841.8×
  105. 105GuadalajaraJalisco, Mexico
    831.8×
  106. 106Addis AbabaAddis Ababa, Ethiopia
    831.8×
  107. 107SalamancaGuanajuato, Mexico
    831.7×
  108. 108PirotCentral Serbia, Serbia
    821.7×
  109. 109Ga-RankuwaNorth West, South Africa
    821.7×
  110. 109ValdiviaLos Ríos Region, Chile
    821.7×
  111. 109Santiago de QuerétaroQuerétaro, Mexico
    821.7×
  112. 112Si Maha PhotPrachin Buri, Thailand
    821.7×
  113. 112CoronelBiobio, Chile
    821.7×
  114. 114Novi PazarCentral Serbia, Serbia
    811.7×
  115. 114BelmopanCayo District, Belize
    811.7×
  116. 114ConcepciónBiobio, Chile
    811.7×
  117. 117Karachilow-cost sensorsSindh, Pakistan
    811.7×
  118. 117LinaresMaule Region, Chile
    811.7×
  119. 119ShanghaiShanghai, China
    811.7×
  120. 120Buri RamBuriram, Thailand
    801.7×
  121. 120Viña del MarValparaiso, Chile
    801.7×
  122. 122ConakryConakry, Guinea
    801.7×
  123. 123Las Palmas de Gran CanariaCanary Islands, Spain
    801.6×
  124. 123LimaLima Province, Peru
    801.6×
  125. 125NišCentral Serbia, Serbia
    801.6×
  126. 125AguascalientesAguascalientes, Mexico
    801.6×
  127. 127RengoO'Higgins Region, Chile
    791.6×
  128. 128AricaArica y Parinacota Region, Chile
    791.6×
  129. 129Santa Cruz de TenerifeCanary Islands, Spain
    791.6×
  130. 129AvilésAsturias, Spain
    791.6×
  131. 129TrentoTrentino-Alto Adige, Italy
    791.6×
  132. 129San Andrés TuxtlaVeracruz, Mexico
    791.6×
  133. 133Tepeji del Río de OcampoHidalgo, Mexico
    791.6×
  134. 134VigoGalicia, Spain
    781.6×
  135. 134PueblaPuebla, Mexico
    781.6×
  136. 136SaraburiSaraburi, Thailand
    781.6×
  137. 136Phra Nakhon Si AyutthayaPhra Nakhon Si Ayutthaya, Thailand
    781.6×
  138. 138KošiceKošice Region, Slovakia
    771.5×
  139. 138Khlong Sam WaBangkok, Thailand
    771.5×
  140. 140CuricóMaule Region, Chile
    771.5×
  141. 141PrešovPrešov Region, Slovakia
    771.5×
  142. 141Lagoslow-cost sensorsLagos, Nigeria
    771.5×
  143. 141Pachuca de SotoHidalgo, Mexico
    771.5×
  144. 144VereenigingGauteng, South Africa
    771.5×
  145. 144TalcaMaule Region, Chile
    771.5×
  146. 146Surat ThaniSurat Thani, Thailand
    771.5×
  147. 146La SerenaCoquimbo Region, Chile
    771.5×
  148. 148AugustówPodlasie, Poland
    761.5×
  149. 148YalaYala, Thailand
    761.5×
  150. 148Hat YaiSongkhla, Thailand
    761.5×
  151. 151ColomboWestern Province, Sri Lanka
    761.5×
  152. 151ChiguayanteBiobio, Chile
    761.5×
  153. 153MiskolcBorsod-Abaúj-Zemplén, Hungary
    761.5×
  154. 153GijónAsturias, Spain
    761.5×
  155. 153San Miguel de AllendeGuanajuato, Mexico
    761.5×
  156. 156San Luis de la PazGuanajuato, Mexico
    751.5×
  157. 156GuanajuatoGuanajuato, Mexico
    751.5×
  158. 156San Pedro de la PazBiobio, Chile
    751.5×
  159. 159Bishkeklow-cost sensorsBishkek, Kyrgyzstan
    751.5×
  160. 160Nakhon PathomNakhon Pathom, Thailand
    751.5×
  161. 161SalorTashkent Region, Uzbekistan
    741.4×
  162. 162Almatylow-cost sensorsAlmaty, Kazakhstan
    731.4×
  163. 163LublinLublin, Poland
    731.4×
  164. 164AshgabatAshgabat, Turkmenistan
    731.4×
  165. 164Saphan SungBangkok, Thailand
    731.4×
  166. 166CoquimboCoquimbo Region, Chile
    721.4×
  167. 167AntofagastaAntofagasta, Chile
    721.4×
  168. 168KazincbarcikaBorsod-Abaúj-Zemplén, Hungary
    721.3×
  169. 169ArrecifeCanary Islands, Spain
    711.3×
  170. 169PrievidzaTrenčín Region, Slovakia
    711.3×
  171. 169CopiapóAtacama, Chile
    711.3×
  172. 172AntananarivoAnalamanga, Madagascar
    711.3×
  173. 172Khlong LuangPathum Thani, Thailand
    711.3×
  174. 172LorientBrittany, France
    711.3×
  175. 172CuernavacaMorelos, Mexico
    711.3×
  176. 176Hua HinPrachuap Khiri Khan, Thailand
    711.3×
  177. 177EdmontonAlberta, Canada
    711.3×
  178. 178LazarevacCentral Serbia, Serbia
    701.3×
  179. 178GuangzhouGuangdong, China
    701.3×
  180. 178DurangoBasque Country, Spain
    701.3×
  181. 181Laudio / LlodioBasque Country, Spain
    701.3×
  182. 181CheyenneWyoming, United States
    701.3×
  183. 181Sai MaiBangkok, Thailand
    701.3×
  184. 184Lak SiBangkok, Thailand
    701.3×
  185. 185TrenčínTrenčín Region, Slovakia
    701.3×
  186. 186JohannesburgGauteng, South Africa
    691.3×
  187. 186Abidjanlow-cost sensorsAbidjan Autonomous District, Ivory Coast
    691.3×
  188. 186Khan Na YaoBangkok, Thailand
    691.3×
  189. 189NarathiwatNarathiwat, Thailand
    691.2×
  190. 189TrnavaTrnava Region, Slovakia
    691.2×
  191. 189BolzanoTrentino-Alto Adige, Italy
    691.2×
  192. 189San Luis PotosíSan Luis Potosí, Mexico
    691.2×
  193. 193Ban Samae DamBangkok, Thailand
    691.2×
  194. 194St. AlbertAlberta, Canada
    681.2×
  195. 195San IsidroCanary Islands, Spain
    681.2×
  196. 195León de los AldamaGuanajuato, Mexico
    681.2×
  197. 197KragujevacCentral Serbia, Serbia
    681.2×
  198. 197Nong KhaemBangkok, Thailand
    681.2×
  199. 199SuwałkiPodlasie, Poland
    681.2×
  200. 199LotaBiobio, Chile
    681.2×

Top 200 of 1,519 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, March 31, 2023, smogrank.com/history/2023-03-31 (accessed 2 Oct 2026).

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