SmogRank / History / May 21, 2025

Most polluted cities on May 21, 2025

2,679 cities ranked by their average PM2.5 over the day; the worst was Navalpattu, India, at 454.0 µg/m³. Each city's own local calendar day.

Bad-air episodes during May 21, 2025. All episodes.

← Navalpattu 454.0 µg/m³ 400 µg/m³15 WHO 24-hour guideline
Every city ranked for May 21, 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. 1NavalpattuTamil Nadu, India
    500+30.3×
  2. 2HualpénBiobio, Chile
    2159.3×
  3. 3BaddiHimachal Pradesh, India
    1937.7×
  4. 4KeonjhargarhOdisha, India
    1907.4×
  5. 5Dubailow-cost sensorsDubai, United Arab Emirates
    1806.4×
  6. 6TlaquepaqueJalisco, Mexico
    1796.3×
  7. 7BathindaPunjab, India
    1776.2×
  8. 8CuddaloreTamil Nadu, India
    1756.0×
  9. 9GobindgarhPunjab, India
    1745.8×
  10. 10KhannaPunjab, India
    1695.4×
  11. 10TalcahuanoBiobio, Chile
    1695.4×
  12. 12Santa Anita - Los FicusLima region, Peru
    1685.3×
  13. 13BawānaDelhi, India
    1675.2×
  14. 14NarelaDelhi, India
    1675.2×
  15. 15AmritsarPunjab, India
    1675.2×
  16. 16LinaresMaule Region, Chile
    1665.2×
  17. 17LudhianaPunjab, India
    1655.1×
  18. 18Aya NagarDelhi, India
    1645.0×
  19. 19MuzaffarnagarUttar Pradesh, India
    1645.0×
  20. 20HanumāngarhRajasthan, India
    1614.7×
  21. 21OsornoLos Lagos Region, Chile
    1614.7×
  22. 22PatiālaPunjab, India
    1614.6×
  23. 22NacimientoBiobio, Chile
    1614.6×
  24. 24DushanbeDushanbe, Tajikistan
    1604.6×
  25. 25Dera MāndiDelhi, India
    1594.5×
  26. 26DelhiDelhi, India
    1584.4×
  27. 27LoniUttar Pradesh, India
    1564.2×
  28. 28San Pedro de la PazBiobio, Chile
    1564.2×
  29. 29Islamabadlow-cost sensorsIslamabad, Pakistan
    1564.1×
  30. 30TalcaMaule Region, Chile
    1554.1×
  31. 31NajafgarhDelhi, India
    1554.1×
  32. 31Hacienda Santa FeJalisco, Mexico
    1554.1×
  33. 33JalandharPunjab, India
    1544.0×
  34. 34CuranilahueBiobio, Chile
    1544.0×
  35. 35ValdiviaLos Ríos Region, Chile
    1533.9×
  36. 36RengoO'Higgins Region, Chile
    1523.8×
  37. 37San CarlosÑuble, Chile
    1523.8×
  38. 38SrinagarJammu and Kashmir, India
    1483.6×
  39. 38SangāreddiTelangana, India
    1483.6×
  40. 40TonkRajasthan, India
    1463.6×
  41. 41CoyhaiqueAysén, Chile
    1453.5×
  42. 42CuricóMaule Region, Chile
    1443.5×
  43. 43ChūruRajasthan, India
    1423.5×
  44. 44ChillánÑuble, Chile
    1413.4×
  45. 45BhelaiChhattisgarh, India
    1403.4×
  46. 46TemucoAraucania, Chile
    1403.4×
  47. 47AlwarRajasthan, India
    1393.4×
  48. 47VapiGujarat, India
    1393.4×
  49. 49AgraUttar Pradesh, India
    1383.4×
  50. 50KhargharMaharashtra, India
    1373.4×
  51. 51RamanathapuramTamil Nadu, India
    1363.3×
  52. 52PithampurMadhya Pradesh, India
    1353.3×
  53. 53ManamaManama, Bahrain
    1353.3×
  54. 53BhiwadiRajasthan, India
    1353.3×
  55. 55BharatpurRajasthan, India
    1343.2×
  56. 56Sri GanganagarRajasthan, India
    1313.2×
  57. 57CholulaPuebla, Mexico
    1313.2×
  58. 58NagpurMaharashtra, India
    1313.2×
  59. 59CauquenesMaule Region, Chile
    1293.1×
  60. 60SuratGujarat, India
    1283.1×
  61. 60KhurjaUttar Pradesh, India
    1283.1×
  62. 62SasarāmBihar, India
    1283.1×
  63. 63BhiwandiMaharashtra, India
    1273.1×
  64. 63AlangadKerala, India
    1273.1×
  65. 65Los ÁngelesBiobio, Chile
    1263.1×
  66. 66JaipurRajasthan, India
    1263.0×
  67. 66GandhinagarGujarat, India
    1263.0×
  68. 68JakartaJakarta, Indonesia
    1253.0×
  69. 69CoronelBiobio, Chile
    1253.0×
  70. 70JhunjhunūnRajasthan, India
    1243.0×
  71. 71AjmerRajasthan, India
    1243.0×
  72. 72KalyānMaharashtra, India
    1233.0×
  73. 73NoidaUttar Pradesh, India
    1233.0×
  74. 74LimaLima Province, Peru
    1233.0×
  75. 75TirupatiAndhra Pradesh, India
    1222.9×
  76. 76León de los AldamaGuanajuato, Mexico
    1212.9×
  77. 77GhāziābādUttar Pradesh, India
    1202.9×
  78. 77ChandigarhChandigarh, India
    1202.9×
  79. 79CallaoCallao, Peru
    1192.9×
  80. 80ConcepciónBiobio, Chile
    1162.8×
  81. 81La UniónLos Ríos Region, Chile
    1162.8×
  82. 82Sawai MadhopurRajasthan, India
    1152.7×
  83. 83PāliRajasthan, India
    1152.7×
  84. 84SantiagoSantiago Metropolitan, Chile
    1142.7×
  85. 85Puente AltoSantiago Metropolitan, Chile
    1132.7×
  86. 86LucknowUttar Pradesh, India
    1122.7×
  87. 87DehradunUttarakhand, India
    1122.7×
  88. 88UnderaGujarat, India
    1112.6×
  89. 89San Francisco De BorjaLima region, Peru
    1102.6×
  90. 90DewasMadhya Pradesh, India
    1092.6×
  91. 91AnantapurAndhra Pradesh, India
    1082.6×
  92. 92VirārMaharashtra, India
    1082.5×
  93. 92SāngliMaharashtra, India
    1082.5×
  94. 92Puerto VarasLos Lagos Region, Chile
    1082.5×
  95. 95AhmedabadGujarat, India
    1062.5×
  96. 96TulancingoHidalgo, Mexico
    1062.5×
  97. 96RancaguaO'Higgins Region, Chile
    1062.5×
  98. 98Puerto MonttLos Lagos Region, Chile
    1052.5×
  99. 99DādriUttar Pradesh, India
    1032.4×
  100. 100MohaliPunjab, India
    1032.4×
  101. 101Mixquiahuala de JuárezHidalgo, Mexico
    1012.4×
  102. 102UdaipurRajasthan, India
    1002.4×
  103. 103RishīkeshUttarakhand, India
    1002.4×
  104. 104PatnaBihar, India
    992.3×
  105. 105AtlixcoPuebla, Mexico
    992.3×
  106. 106GayaBihar, India
    992.3×
  107. 107TalaganteSantiago Metropolitan, Chile
    992.3×
  108. 108DausaRajasthan, India
    992.3×
  109. 109TirupparangunramTamil Nadu, India
    982.3×
  110. 110BulandshahrUttar Pradesh, India
    982.3×
  111. 110ShenyangLiaoning, China
    982.3×
  112. 112SīkarRajasthan, India
    972.3×
  113. 113KanpurUttar Pradesh, India
    972.3×
  114. 113Tepeji del Río de OcampoHidalgo, Mexico
    972.3×
  115. 115VijayawadaAndhra Pradesh, India
    972.2×
  116. 116JabalpurMadhya Pradesh, India
    972.2×
  117. 117Ban Talat BuengChon Buri, Thailand
    962.2×
  118. 118SaijōEhime, Japan
    962.2×
  119. 119AntofagastaAntofagasta, Chile
    962.2×
  120. 120ŌtsukiYamanashi, Japan
    952.2×
  121. 120Wadgaon KolhatiMaharashtra, India
    952.2×
  122. 122Puerto AysénAysén, Chile
    952.2×
  123. 123Naucalpan de JuárezMéxico, Mexico
    942.2×
  124. 124Ciudad NezahualcoyotlMéxico, Mexico
    942.1×
  125. 125ChiguayanteBiobio, Chile
    942.1×
  126. 126PrayagrajUttar Pradesh, India
    932.1×
  127. 127YamanashiYamanashi, Japan
    932.1×
  128. 128PueblaPuebla, Mexico
    932.1×
  129. 129TiruchirappalliTamil Nadu, India
    922.1×
  130. 130VrindāvanUttar Pradesh, India
    922.1×
  131. 130HājīpurBihar, India
    922.1×
  132. 132Tottori-shiTottori, Japan
    912.1×
  133. 132MonterreyNuevo León, Mexico
    912.1×
  134. 134TomiokaGunma, Japan
    912.0×
  135. 134SalamancaGuanajuato, Mexico
    912.0×
  136. 136AguascalientesAguascalientes, Mexico
    912.0×
  137. 136QuthbullapurTelangana, India
    912.0×
  138. 138Cadereyta JiménezNuevo León, Mexico
    902.0×
  139. 139RourkelaOdisha, India
    902.0×
  140. 140Ciudad Benito JuárezNuevo León, Mexico
    902.0×
  141. 141NashikMaharashtra, India
    902.0×
  142. 141HyderabadTelangana, India
    902.0×
  143. 141SabaeFukui, Japan
    902.0×
  144. 141ConcónValparaiso, Chile
    902.0×
  145. 145MeerutUttar Pradesh, India
    902.0×
  146. 145TocopillaAntofagasta, Chile
    902.0×
  147. 147ThāneMaharashtra, India
    892.0×
  148. 148NanNan, Thailand
    892.0×
  149. 149ShibukawaGunma, Japan
    892.0×
  150. 149Kodamachō-kodamaminamiSaitama, Japan
    892.0×
  151. 149KiryūGunma, Japan
    892.0×
  152. 152TlaxcalaTlaxcala, Mexico
    892.0×
  153. 153AkolaMaharashtra, India
    892.0×
  154. 153NiihamaEhime, Japan
    892.0×
  155. 155RānipetTamil Nadu, India
    881.9×
  156. 155MangaluruKarnataka, India
    881.9×
  157. 155La SerenaCoquimbo Region, Chile
    881.9×
  158. 158Mexico CityMexico City, Mexico
    881.9×
  159. 159ChittorgarhRajasthan, India
    881.9×
  160. 159MikuniFukui, Japan
    881.9×
  161. 159Santa CatarinaNuevo León, Mexico
    881.9×
  162. 162KofuYamanashi, Japan
    871.9×
  163. 163JōetsuNiigata, Japan
    871.9×
  164. 164AmravatiMaharashtra, India
    871.9×
  165. 164ChichibuSaitama, Japan
    871.9×
  166. 166MimaTokushima, Japan
    871.9×
  167. 167MorohongōSaitama, Japan
    861.9×
  168. 168CoquimboCoquimbo Region, Chile
    861.9×
  169. 169YoriiSaitama, Japan
    861.9×
  170. 169KagaIshikawa, Japan
    861.9×
  171. 171BhopalMadhya Pradesh, India
    861.9×
  172. 172KigaliKigali, Rwanda
    851.8×
  173. 172FīrozābādUttar Pradesh, India
    851.8×
  174. 172ŌmeTokyo, Japan
    851.8×
  175. 172MenumaSaitama, Japan
    851.8×
  176. 172HannōSaitama, Japan
    851.8×
  177. 177SanoTochigi, Japan
    851.8×
  178. 177NakanojōGunma, Japan
    851.8×
  179. 177QuinteroValparaiso, Chile
    851.8×
  180. 177ShikokuchūōEhime, Japan
    851.8×
  181. 181BhāgalpurBihar, India
    851.8×
  182. 181ToyamaToyama, Japan
    851.8×
  183. 183GwaliorMadhya Pradesh, India
    851.8×
  184. 183AgeoSaitama, Japan
    851.8×
  185. 183Pachuca de SotoHidalgo, Mexico
    851.8×
  186. 183IrumaSaitama, Japan
    851.8×
  187. 187IndoreMadhya Pradesh, India
    851.8×
  188. 187UozuToyama, Japan
    851.8×
  189. 187OnoFukui, Japan
    851.8×
  190. 187ImaichiTochigi, Japan
    851.8×
  191. 187GyōdaSaitama, Japan
    851.8×
  192. 187San Martin Texmelucan de LabastidaPuebla, Mexico
    851.8×
  193. 193SuwaNagano, Japan
    841.8×
  194. 193TehuacánPuebla, Mexico
    841.8×
  195. 193TonamiToyama, Japan
    841.8×
  196. 196Villa Poeta José Gálvez BarrenecheaLima region, Peru
    841.8×
  197. 196ShirakawaFukushima, Japan
    841.8×
  198. 198ItoigawaNiigata, Japan
    841.8×
  199. 199BāghpatUttar Pradesh, India
    841.8×
  200. 199HashimaGifu, Japan
    841.8×

Top 200 of 2,679 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

Not covered: the government monitoring networks of China and Turkey, which publish no terms that let us reuse their readings. Most cities there are missing from this board, not clean. Why.

Use this board

SmogRank, most polluted cities, PM2.5, May 21, 2025, smogrank.com/history/2025-05-21 (accessed 2 Oct 2026).

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