SmogRank / Thailand / Khon Kaen / Khon Kaen

Khon Kaen, month by month

Khon Kaen has a measured daily mean on 519 days since 26 March 2023. Its worst month was February 2024, at 123 US AQI (44.6 µg/m³), 45th of 2,486 cities on that month's world ranking. Its cleanest was September 2026, at 67 US AQI (17.7 µg/m³).

Every month since 2023

202683 so far203 days measured242nd of 2,798 in the world
Jan19 daysFeb98#202Mar19 daysApr14 daysMay77#237Jun67#278Jul3 daysAug67#303Sep67#314Oct73#106
2025too few days for a mean (a year needs 256)114 days measured
Jan4 daysFeb109#114Mar19 daysApr14 daysMay10 daysJun9 daysJulnoneAugnoneSep12 daysOct4 daysNov5 daysDec15 days
2024too few days for a mean (a year needs 257)151 days measured
Jan82#169Feb123#45Mar19 daysApr119#43May76#115Jun12 daysJul10 daysAug4 daysSep1 dayOctnoneNov2 daysDecnone
2023too few days for a mean (a year needs 256)51 days measured
JanFebMar6 daysApr13 daysMay12 daysJun10 daysJul5 daysAug3 daysSep2 daysOctnoneNovnoneDecnone
Each square is a month's mean PM2.5 in US AQI from Khon Kaen's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Khon Kaen marked; each year, the year's. A dashed square is the running month, so far.
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

Months without a mean, and why

33 months
MonthWhy
Jul 20263 of 31 days measured; a month needs 22. The others: 28 with under 18 hours of readings or readings that failed our checks.
Apr 202614 of 30 days measured; a month needs 21. The others: 16 with under 18 hours of readings or readings that failed our checks.
Mar 202619 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
Jan 202619 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
Dec 202515 of 31 days measured; a month needs 22. The others: 16 with under 18 hours of readings or readings that failed our checks.
Nov 20255 of 30 days measured; a month needs 21. The others: 25 with under 18 hours of readings or readings that failed our checks.
Oct 20254 of 31 days measured; a month needs 22. The others: 27 with under 18 hours of readings or readings that failed our checks.
Sep 202512 of 30 days measured; a month needs 21. The others: 18 with under 18 hours of readings or readings that failed our checks.
Aug 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jul 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jun 20259 of 30 days measured; a month needs 21. The others: 21 with under 18 hours of readings or readings that failed our checks.
May 202510 of 31 days measured; a month needs 22. The others: 21 with under 18 hours of readings or readings that failed our checks.
Apr 202514 of 30 days measured; a month needs 21. The others: 16 with under 18 hours of readings or readings that failed our checks.
Mar 202519 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
Jan 20254 of 31 days measured; a month needs 22. The others: 27 with under 18 hours of readings or readings that failed our checks.
Dec 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 20242 of 30 days measured; a month needs 21. The others: 28 with under 18 hours of readings or readings that failed our checks.
Oct 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Sep 20241 of 30 days measured; a month needs 21. The others: 29 with under 18 hours of readings or readings that failed our checks.
Aug 20244 of 31 days measured; a month needs 22. The others: 27 with under 18 hours of readings or readings that failed our checks.
Jul 202410 of 31 days measured; a month needs 22. The others: 21 with under 18 hours of readings or readings that failed our checks.
Jun 202412 of 30 days measured; a month needs 21. The others: 18 with under 18 hours of readings or readings that failed our checks.
Mar 202419 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
Dec 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 2023No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Oct 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Sep 20232 of 30 days measured; a month needs 21. The others: 28 with under 18 hours of readings or readings that failed our checks.
Aug 20233 of 31 days measured; a month needs 22. The others: 28 with under 18 hours of readings or readings that failed our checks.
Jul 20235 of 31 days measured; a month needs 22. The others: 1 missing from OpenAQ's archive, 25 with under 18 hours of readings or readings that failed our checks.
Jun 202310 of 30 days measured; a month needs 21. The others: 20 with under 18 hours of readings or readings that failed our checks.
May 202312 of 31 days measured; a month needs 22. The others: 19 with under 18 hours of readings or readings that failed our checks.
Apr 202313 of 30 days measured; a month needs 21. The others: 2 missing from OpenAQ's archive, 15 with under 18 hours of readings or readings that failed our checks.
Mar 20236 of 31 days measured; a month needs 22.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Khon Kaen's worst months

MonthUS AQIDays measuredWorld rank
February 2024 12344.6 µg/m³22 of 2945thof 2,486
April 2024 11943.0 µg/m³28 of 3043rdof 2,520
February 2025 10938.8 µg/m³22 of 28114thof 2,633
February 2026 9834.5 µg/m³24 of 28202ndof 2,866
January 2024 8225.8 µg/m³23 of 31169thof 2,385
May 2026 7723.2 µg/m³25 of 31237thof 2,874

Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.

Khon Kaen's worst days

DayUS AQIEpisode
25 Mar 2025 17691.6 µg/m³Thailand and Laos, March 2025
26 Mar 2025 17589.9 µg/m³Thailand and Laos, March 2025
26 Jan 2025 16879.7 µg/m³Northern Thailand, January 2025
27 Mar 2025 16676.4 µg/m³Thailand and Laos, March 2025
24 Jan 2025 16372.5 µg/m³Northern Thailand, January 2025
17 Jan 2026 16170.4 µg/m³–
25 Jan 2025 16169.8 µg/m³Northern Thailand, January 2025
9 Feb 2024 16068.0 µg/m³–
5 Apr 2026 15967.0 µg/m³–
7 Apr 2023 15865.7 µg/m³–

Daily means, the highest since 26 Mar 2023; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.

Use this history

SmogRank, PM2.5 monthly and daily means, Khon Kaen, Thailand, 26 Mar 2023 – 12 Oct 2026. Monitor data from Air4Thai via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/th/khon-kaen/history (accessed 13 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Khon Kaen now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-13 00:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).