SmogRank / Japan / Gifu / Toki
Toki, month by month
Toki has a measured daily mean on 865 days since 28 July 2023. Its worst month was April 2024, at 63 US AQI (15.7 µg/m³), 377th of 2,520 cities on that month's world ranking. Its cleanest was January 2026, at 41 US AQI (7.4 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 |
|---|---|
| May 2025 | 17 of 31 days measured; a month needs 22. The others: 14 with under 18 hours of readings or readings that failed our checks. |
| Apr 2025 | No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks. |
| Mar 2025 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Feb 2025 | No day measured. The others: 28 with under 18 hours of readings or readings that failed our checks. |
| Feb 2024 | 14 of 29 days measured; a month needs 21. The others: 1 missing from OpenAQ's archive, 14 with under 18 hours of readings or readings that failed our checks. |
| Jan 2024 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Dec 2023 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Nov 2023 | 5 of 30 days measured; a month needs 21. The others: 25 with under 18 hours of readings or readings that failed our checks. |
| Oct 2023 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Sep 2023 | 6 of 30 days measured; a month needs 21. The others: 24 with under 18 hours of readings or readings that failed our checks. |
| Aug 2023 | 8 of 31 days measured; a month needs 22. The others: 23 with under 18 hours of readings or readings that failed our checks. |
| Jul 2023 | 3 of 31 days measured; a month needs 22. The others: 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.
Toki's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| April 2024 | 6315.7 µg/m³ | 377thof 2,520 | Japan and South Korea, April 2024 |
| August 2025 | 6114.5 µg/m³ | 399thof 2,901 | Japan, 4 to 5 August 2025 |
| July 2025 | 5813.0 µg/m³ | 639thof 2,889 | Japan and South Korea, June and July 2025 |
| July 2026 | 5712.2 µg/m³ | 865thof 2,784 | – |
| June 2025 | 5712.1 µg/m³ | 792ndof 2,508 | Japan and South Korea, June and July 2025 |
| September 2024 | 5511.4 µg/m³ | 309thof 2,010 | – |
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.
Toki's worst days
| Day | US AQI | Episode |
|---|---|---|
| 9 Jul 2025 | 9934.8 µg/m³ | Japan and South Korea, June and July 2025 |
| 19 Apr 2024 | 9934.6 µg/m³ | Japan and South Korea, April 2024 |
| 18 Apr 2024 | 8929.3 µg/m³ | Japan and South Korea, April 2024 |
| 4 Aug 2025 | 8527.3 µg/m³ | Japan, 4 to 5 August 2025 |
| 17 Apr 2024 | 8426.7 µg/m³ | Japan and South Korea, April 2024 |
| 5 Jul 2025 | 8426.7 µg/m³ | Japan and South Korea, June and July 2025 |
| 5 Aug 2025 | 8326.5 µg/m³ | Japan, 4 to 5 August 2025 |
| 2 Jul 2025 | 8226.0 µg/m³ | Japan and South Korea, June and July 2025 |
| 21 May 2025 | 8225.5 µg/m³ | Japan, May 2025 |
| 20 Apr 2024 | 8024.4 µg/m³ | Japan and South Korea, April 2024 |
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, Toki, 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/toki/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.
Toki now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 17:07 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).