SmogRank / Japan / Hyōgo / Toyooka

Toyooka, month by month

Toyooka has a measured daily mean on 1,160 days since 29 July 2023. Its worst month was July 2025, at 58 US AQI (13.0 µg/m³), 639th of 2,889 cities on that month's world ranking. Its cleanest was October 2024, at 31 US AQI (5.5 µg/m³). 2025 averaged 52 US AQI (9.4 µg/m³), against 41 US AQI (7.3 µg/m³) in 2024.

Every month since 2023

2023too few days for a mean (a year needs 256)155 days measured
Each square is a month's mean PM2.5 in US AQI from Toyooka'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 Toyooka 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

1 month
MonthWhy
Jul 20233 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.

Toyooka's worst months

MonthUS AQIDays measuredWorld rankEpisode
July 2025 5813.0 µg/m³31 of 31639thof 2,889Japan and South Korea, June and July 2025
April 2025 5812.6 µg/m³30 of 30696thof 2,951Japan and South Korea, April 2025
March 2026 5712.3 µg/m³29 of 311,154thof 2,971Japan and South Korea, March 2026
July 2026 5611.9 µg/m³31 of 31909thof 2,784Japan and South Korea, July 2026
June 2025 5611.7 µg/m³30 of 30861stof 2,508Japan and South Korea, June and July 2025
May 2025 5511.3 µg/m³31 of 31658thof 2,826Japan, May 2025

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.

Toyooka's worst days

DayUS AQIEpisode
2 Jul 2025 10537.1 µg/m³Japan and South Korea, June and July 2025
18 Apr 2024 9633.5 µg/m³Japan and South Korea, April 2024
4 Jul 2025 9432.0 µg/m³Japan and South Korea, June and July 2025
24 Mar 2026 9130.6 µg/m³Japan and South Korea, March 2026
25 Apr 2025 8929.3 µg/m³Japan and South Korea, April 2025
26 Mar 2025 8829.0 µg/m³Japan and South Korea, March 2025
31 Jan 2025 8627.7 µg/m³Japan and South Korea, 31 January to 1 February 2025
21 Jul 2026 8627.7 µg/m³Japan and South Korea, July 2026
29 Mar 2026 8426.6 µg/m³Japan and South Korea, March 2026
21 May 2025 8125.3 µg/m³Japan, May 2025

Daily means, the highest since 29 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, Toyooka, Japan, 29 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/toyooka/history (accessed 12 Oct 2026).

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

Updated 2026-10-12 20:07 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).