SmogRank / Thailand / Nakhon Nayok / Nakhon Nayok
Nakhon Nayok, month by month
Nakhon Nayok has a measured daily mean on 677 days since 5 January 2024. Its worst month was February 2024, at 89 US AQI (29.3 µg/m³), 110th of 2,486 cities on that month's world ranking. Its cleanest was June 2026, at 44 US AQI (8.0 µg/m³).
Every month since 2024
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
13 months
| Month | Why |
|---|---|
| Jul 2026 | 3 of 31 days measured; a month needs 22. The others: 28 with under 18 hours of readings or readings that failed our checks. |
| Nov 2025 | 12 of 30 days measured; a month needs 21. The others: 18 with under 18 hours of readings or readings that failed our checks. |
| Oct 2025 | 10 of 31 days measured; a month needs 22. The others: 21 with under 18 hours of readings or readings that failed our checks. |
| Aug 2025 | 6 of 31 days measured; a month needs 22. The others: 25 with under 18 hours of readings or readings that failed our checks. |
| Jul 2025 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Jan 2025 | 4 of 31 days measured; a month needs 22. The others: 27 with under 18 hours of readings or readings that failed our checks. |
| Dec 2024 | 1 of 31 days measured; a month needs 22. The others: 30 with under 18 hours of readings or readings that failed our checks. |
| Nov 2024 | 3 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks. |
| Oct 2024 | 2 of 31 days measured; a month needs 22. The others: 29 with under 18 hours of readings or readings that failed our checks. |
| Sep 2024 | 5 of 30 days measured; a month needs 21. The others: 25 with under 18 hours of readings or readings that failed our checks. |
| Aug 2024 | 17 of 31 days measured; a month needs 22. The others: 14 with under 18 hours of readings or readings that failed our checks. |
| Jul 2024 | 19 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks. |
| Mar 2024 | 20 of 31 days measured; a month needs 22. The others: 11 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.
Nakhon Nayok's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| February 2024 | 8929.3 µg/m³ | 110thof 2,486 | Thailand, February 2024 |
| April 2024 | 8829.1 µg/m³ | 82ndof 2,520 | Thailand and Laos, April and May 2024 |
| March 2025 | 8527.3 µg/m³ | 366thof 2,862 | Thailand and Laos, March 2025 |
| January 2024 | 8426.9 µg/m³ | 147thof 2,385 | – |
| April 2026 | 8326.1 µg/m³ | 287thof 2,941 | – |
| February 2025 | 8225.7 µg/m³ | 271stof 2,633 | – |
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.
Nakhon Nayok's worst days
| Day | US AQI | Episode |
|---|---|---|
| 11 Apr 2024 | 15358.8 µg/m³ | – |
| 24 Jan 2025 | 15256.8 µg/m³ | Northern Thailand, January 2025 |
| 25 Mar 2025 | 14151.7 µg/m³ | Thailand and Laos, March 2025 |
| 26 Mar 2025 | 14051.4 µg/m³ | Thailand and Laos, March 2025 |
| 24 Mar 2025 | 13850.4 µg/m³ | Thailand and Laos, March 2025 |
| 15 Feb 2024 | 13549.2 µg/m³ | Thailand, February 2024 |
| 16 Feb 2024 | 13448.7 µg/m³ | Thailand, February 2024 |
| 12 Apr 2024 | 13348.4 µg/m³ | – |
| 25 Jan 2025 | 12444.8 µg/m³ | Northern Thailand, January 2025 |
| 31 Jan 2024 | 12344.5 µg/m³ | – |
Daily means, the highest since 5 Jan 2024; 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, Nakhon Nayok, Thailand, 5 Jan 2024 – 12 Oct 2026. Monitor data from Air4Thai via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/th/nakhon-nayok/history (accessed 13 Oct 2026).
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.
Nakhon Nayok now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-13 03:07 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).