SmogRank / Thailand / Lopburi / Lop Buri

Lop Buri, month by month

Lop Buri has a measured daily mean on 742 days since 1 January 2023. Its worst month was February 2024, at 120 US AQI (43.4 µg/m³), 49th of 2,486 cities on that month's world ranking. Its cleanest was June 2026, at 50 US AQI (9.0 µg/m³).

Every month since 2023

202675 so far248 days measured321st of 2,798 in the world
Jan98#132Feb88#269Mar87#317Apr118#105May61#449Jun50#813Jul3 daysAug54#786Sep55#557Oct62#220
2025too few days for a mean (a year needs 256)215 days measured
Jan5 daysFeb112#96Mar112#158Apr95#144May63#389Jun58#662JulnoneAug6 daysSep52#776Oct10 daysNov12 daysDec72#486
2024too few days for a mean (a year needs 257)194 days measured
Jan21 daysFeb120#49Mar20 daysApr111#49May76#115Jun58#284Jul18 daysAug17 daysSep5 daysOct2 daysNov3 daysDecnone
2023too few days for a mean (a year needs 256)85 days measured
Jan86#76Feb2 daysMar9 daysApr19 daysMay15 daysJun9 daysJul5 daysAug1 daySep3 daysOctnoneNovnoneDecnone
Each square is a month's mean PM2.5 in US AQI from Lop Buri'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 Lop Buri 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

25 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.
Nov 202512 of 30 days measured; a month needs 21. The others: 18 with under 18 hours of readings or readings that failed our checks.
Oct 202510 of 31 days measured; a month needs 22. The others: 21 with under 18 hours of readings or readings that failed our checks.
Aug 20256 of 31 days measured; a month needs 22. The others: 25 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.
Jan 20255 of 31 days measured; a month needs 22. The others: 26 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 20243 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks.
Oct 20242 of 31 days measured; a month needs 22. The others: 29 with under 18 hours of readings or readings that failed our checks.
Sep 20245 of 30 days measured; a month needs 21. The others: 25 with under 18 hours of readings or readings that failed our checks.
Aug 202417 of 31 days measured; a month needs 22. The others: 14 with under 18 hours of readings or readings that failed our checks.
Jul 202418 of 31 days measured; a month needs 22. The others: 13 with under 18 hours of readings or readings that failed our checks.
Mar 202420 of 31 days measured; a month needs 22. The others: 11 with under 18 hours of readings or readings that failed our checks.
Jan 202421 of 31 days measured; a month needs 22. The others: 10 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 20233 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks.
Aug 20231 of 31 days measured; a month needs 22. The others: 30 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 20239 of 30 days measured; a month needs 21. The others: 21 with under 18 hours of readings or readings that failed our checks.
May 202315 of 31 days measured; a month needs 22. The others: 16 with under 18 hours of readings or readings that failed our checks.
Apr 202319 of 30 days measured; a month needs 21. The others: 2 missing from OpenAQ's archive, 9 with under 18 hours of readings or readings that failed our checks.
Mar 20239 of 31 days measured; a month needs 22. The others: 19 missing from OpenAQ's archive, 3 with under 18 hours of readings or readings that failed our checks.
Feb 20232 of 28 days measured; a month needs 20. The others: 25 missing from OpenAQ's archive, 1 with under 18 hours of readings or readings that failed our checks.

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

Lop Buri's worst months

MonthUS AQIDays measuredWorld rankEpisode
February 2024 12043.4 µg/m³22 of 2949thof 2,486Thailand, February 2024
April 2026 11842.6 µg/m³30 of 30105thof 2,941–
February 2025 11240.0 µg/m³28 of 2896thof 2,633–
March 2025 11240.0 µg/m³27 of 31158thof 2,862Thailand and Laos, March 2025
April 2024 11139.6 µg/m³28 of 3049thof 2,520–
January 2026 9834.2 µg/m³31 of 31132ndof 2,617–

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.

Lop Buri's worst days

DayUS AQIEpisode
25 Jan 2025 17893.8 µg/m³Northern Thailand, January 2025
24 Jan 2025 17792.1 µg/m³Northern Thailand, January 2025
16 Feb 2024 17082.4 µg/m³Thailand, February 2024
26 Jan 2025 17082.1 µg/m³Northern Thailand, January 2025
24 Mar 2025 17082.1 µg/m³Thailand and Laos, March 2025
15 Feb 2024 16677.6 µg/m³Thailand, February 2024
16 Apr 2023 16372.1 µg/m³Thailand, April 2023
25 Mar 2025 16372.1 µg/m³Thailand and Laos, March 2025
1 Feb 2023 16270.8 µg/m³–
6 Apr 2026 16170.3 µg/m³–

Daily means, the highest since 1 Jan 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, Lop Buri, Thailand, 1 Jan 2023 – 12 Oct 2026. Monitor data from Air4Thai via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/th/lop-buri/history (accessed 13 Oct 2026).

Download chart (PNG)

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.

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

Updated 2026-10-13 01:07 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).