SmogRank / Japan / Oita / Beppu
Beppu, month by month
Beppu has a measured daily mean on 969 days since 28 July 2023. Its worst month was March 2025, at 64 US AQI (16.0 µg/m³), 860th of 2,862 cities on that month's world ranking. Its cleanest was August 2026, at 35 US AQI (6.3 µg/m³).
Every month since 2023
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
12 months
| Month | Why |
|---|---|
| Nov 2024 | 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 2024 | 9 of 31 days measured; a month needs 22. The others: 22 with under 18 hours of readings or readings that failed our checks. |
| Sep 2024 | 15 of 30 days measured; a month needs 21. The others: 15 with under 18 hours of readings or readings that failed our checks. |
| Aug 2024 | 21 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks. |
| Jul 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. |
| Mar 2024 | 20 of 31 days measured; a month needs 22. The others: 1 missing from OpenAQ's archive, 10 with under 18 hours of readings or readings that failed our checks. |
| Feb 2024 | 12 of 29 days measured; a month needs 21. The others: 1 missing from OpenAQ's archive, 16 with under 18 hours of readings or readings that failed our checks. |
| Jan 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. |
| Dec 2023 | 18 of 31 days measured; a month needs 22. The others: 13 with under 18 hours of readings or readings that failed our checks. |
| Sep 2023 | 20 of 30 days measured; a month needs 21. The others: 10 with under 18 hours of readings or readings that failed our checks. |
| Aug 2023 | 19 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks. |
| Jul 2023 | 2 of 31 days measured; a month needs 22. The others: 2 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.
Beppu's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| March 2025 | 6416.0 µg/m³ | 860thof 2,862 | Japan and South Korea, March 2025 Japan and South Korea, February and March 2025 |
| April 2025 | 6013.7 µg/m³ | 606thof 2,951 | – |
| August 2025 | 5913.5 µg/m³ | 493rdof 2,901 | – |
| June 2025 | 5913.4 µg/m³ | 612thof 2,508 | Japan and South Korea, June and July 2025 Japan, June 2025 |
| July 2026 | 5813.1 µg/m³ | 712thof 2,784 | Japan and South Korea, July 2026 |
| November 2025 | 5813.0 µg/m³ | 684thof 2,715 | – |
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.
Beppu's worst days
| Day | US AQI | Episode |
|---|---|---|
| 3 Jul 2025 | 12846.6 µg/m³ | Japan and South Korea, June and July 2025 |
| 4 Jul 2025 | 12444.8 µg/m³ | Japan and South Korea, June and July 2025 |
| 5 Jul 2025 | 11139.6 µg/m³ | Japan and South Korea, June and July 2025 |
| 1 Mar 2025 | 10336.5 µg/m³ | Japan and South Korea, February and March 2025 |
| 21 Jul 2026 | 10135.7 µg/m³ | Japan and South Korea, July 2026 |
| 2 Mar 2025 | 9834.2 µg/m³ | Japan and South Korea, February and March 2025 |
| 29 Mar 2026 | 9130.7 µg/m³ | Japan and South Korea, March 2026 |
| 19 Jul 2026 | 9030.0 µg/m³ | Japan and South Korea, July 2026 |
| 26 Mar 2025 | 8728.3 µg/m³ | Japan and South Korea, March 2025 |
| 9 Jul 2025 | 8628.0 µg/m³ | Japan and South Korea, June and July 2025 |
Daily means, the highest since 28 Jul 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, Beppu, Japan, 28 Jul 2023 – 12 Oct 2026. Monitor data from Ministry of the Environment Air Pollutant Wide Area Monitoring System via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/jp/beppu/history (accessed 12 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.
Beppu now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 18:07 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).