All 3,290 cities by unhealthy days, last 30 days

Every city with enough measurements in this window, worst first.

CPCB in India: no readings since 12 Oct (488 monitors). EEA in Spain: no readings since 13 Oct (310 monitors). Their cities show older figures or are missing from this board, not clean.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Cities with the same share are ordered by more unhealthy days, then by the higher average.

=2569HudsonvilleMichigan, United States 0%0 of 30
=2569Saint PaulMinnesota, United States 0%0 of 30
=2569OmahaNebraska, United States 0%0 of 30
=2569CanonsburgPennsylvania, United States 0%0 of 30
=2569LebanonPennsylvania, United States 0%0 of 30
=2569PhoenixArizona, United States 0%0 of 30
=2569AtascaderoCalifornia, United States 0%0 of 30
=2569CrestlineCalifornia, United States 0%0 of 29
=2569SebastopolCalifornia, United States 0%0 of 30
=2569WindsorCalifornia, United States 0%0 of 21
=2569EugeneOregon, United States 0%0 of 30
=2569PortlandOregon, United States 0%0 of 30
=2569StaytonOregon, United States 0%0 of 30
=2569BountifulUtah, United States 0%0 of 29
=2569Brigham CityUtah, United States 0%0 of 30
=2569Moses LakeWashington, United States 0%0 of 26
=2569LangfordBritish Columbia, Canada 0%0 of 29
=2618Veľká LomnicaPrešov Region, Slovakia 0%0 of 25
=2618KochaniKochani, North Macedonia 0%0 of 24
=2618UedaNagano, Japan 0%0 of 30
=2618TōganeChiba, Japan 0%0 of 27
=2618SapporoHokkaido, Japan 0%0 of 30
=2618SheringhamEngland, United Kingdom 0%0 of 30
=2618PeterboroughEngland, United Kingdom 0%0 of 30
=2618LoughboroughEngland, United Kingdom 0%0 of 30
=2618LiverpoolEngland, United Kingdom 0%0 of 30
=2618HayesEngland, United Kingdom 0%0 of 30
=2618DerbyEngland, United Kingdom 0%0 of 30
=2618Lübecklast full day 10 OctSchleswig-Holstein, Germany 0%0 of 26
=2618Carlowlast full day 9 OctLeinster, Ireland 0%0 of 22
=2618VannesBrittany, France 0%0 of 30
=2618TarbesOccitanie, France 0%0 of 30
=2618MontaubanOccitanie, France 0%0 of 30
=2618CastresOccitanie, France 0%0 of 30
=2618AngoulêmeNew Aquitaine, France 0%0 of 30
=2618WashingtonDistrict of Columbia, United States 0%0 of 30
=2618BartowFlorida, United States 0%0 of 30
=2618GainesvilleFlorida, United States 0%0 of 30
=2618Pompano BeachFlorida, United States 0%0 of 27
=2618St. PetersburgFlorida, United States 0%0 of 30
=2618Smithvillelast full day 9 OctNew Jersey, United States 0%0 of 26
=2618HopewellVirginia, United States 0%0 of 21
=2618Des PlainesIllinois, United States 0%0 of 30
=2618Ann ArborMichigan, United States 0%0 of 30
=2618BlaineMinnesota, United States 0%0 of 30
=2618MarshallMinnesota, United States 0%0 of 30
=2618Saint MichaelMinnesota, United States 0%0 of 27
=2618Grand IslandNebraska, United States 0%0 of 26
=2618EwingNew Jersey, United States 0%0 of 28
=2618ScrantonPennsylvania, United States 0%0 of 30
=2618Green BayWisconsin, United States 0%0 of 27
=2618Weirtonlast full day 10 OctWest Virginia, United States 0%0 of 27
=2618Coeur d'AleneIdaho, United States 0%0 of 30
=2618MadrasOregon, United States 0%0 of 30
=2618OremUtah, United States 0%0 of 30
=2618BurienWashington, United States 0%0 of 30
=2618ChehalisWashington, United States 0%0 of 30
=2618BrantfordOntario, Canada 0%0 of 30
=2618CoquitlamBritish Columbia, Canada 0%0 of 30
=2618LondonOntario, Canada 0%0 of 30
=2618Sherwood ParkAlberta, Canada 0%0 of 29
=2618FujiyoshidaYamanashi, Japan 0%0 of 30
=2618KyōtangoKyoto, Japan 0%0 of 30
=2664GeroGifu, Japan 0%0 of 30
=2664OgawamachiSaitama, Japan 0%0 of 30
=2664Niitsu-honchōNiigata, Japan 0%0 of 29
=2664MiyazuKyoto, Japan 0%0 of 30
=2664NorwichEngland, United Kingdom 0%0 of 30
=2664Burton upon TrentEngland, United Kingdom 0%0 of 30
=2664Ashton-under-Lynelast full day 11 OctEngland, United Kingdom 0%0 of 28
=2664Trappenkamplast full day 10 OctSchleswig-Holstein, Germany 0%0 of 24
=2664TauberbischofsheimBaden-Wurttemberg, Germany 0%0 of 30
=2664Kiellast full day 10 OctSchleswig-Holstein, Germany 0%0 of 26
=2664Flensburglast full day 10 OctSchleswig-Holstein, Germany 0%0 of 26
=2664EnniscorthyLeinster, Ireland 0%0 of 30
=2664PassyAuvergne-Rhône-Alpes, France 0%0 of 30
=2664Montceau-les-MinesBourgogne-Franche-Comté, France 0%0 of 30
=2664Ajacciolast full day 7 OctCorsica, France 0%0 of 21
=2664ColumbusIndiana, United States 0%0 of 26
=2664KearneyMissouri, United States 0%0 of 30
=2664KingsportTennessee, United States 0%0 of 30
=2664RichmondVirginia, United States 0%0 of 30
=2664SalemVirginia, United States 0%0 of 26
=2664CaryIllinois, United States 0%0 of 30
=2664BurnsvilleMinnesota, United States 0%0 of 28
=2664ShakopeeMinnesota, United States 0%0 of 26
=2664PatersonNew Jersey, United States 0%0 of 30
=2664New AlbanyOhio, United States 0%0 of 30
=2664JohnstownPennsylvania, United States 0%0 of 30
=2664Camp Verdelast full day 11 OctArizona, United States 0%0 of 27
=2664Fort CollinsColorado, United States 0%0 of 28
=2664OntarioOregon, United States 0%0 of 27
=2664The DallesOregon, United States 0%0 of 30
=2664LaceyWashington, United States 0%0 of 30
=2664PullmanWashington, United States 0%0 of 30
=2664NewmarketOntario, Canada 0%0 of 28
=2664Port CoquitlamBritish Columbia, Canada 0%0 of 30
=2664TerraceBritish Columbia, Canada 0%0 of 29
=2664WindsorOntario, Canada 0%0 of 30
=2664L'Ancienne-LoretteQuebec, Canada 0%0 of 30

What stands behind each figure: Checked at 2+ sites One reference monitor Low-cost sensors About these marks

Low-cost sensors: consumer units, counted only in cities with no government-grade monitor; they read close to reference monitors on the whole, but 15 to 25% high in humid air. How we use them.

Good0–50

Moderate51–100

Unhealthy for 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

Not covered: the government monitoring networks of China, Turkey and Iran, which publish only on their own websites. We are building the reader for China's network. The networks of Turkey and Iran don't answer requests from outside their countries, so we can't read them. Most cities there are missing from this board, not clean. Why.

Use this board

SmogRank, all cities ranked by unhealthy days (PM2.5), last 30 days to 14 Oct 2026, 07:00 UTC: each city's share of its measured days with a daily mean over 35.4 µg/m³, cities measured on 21 or more of the 30 days. Monitor data from national networks via OpenAQ and the publishers listed at smogrank.com/sources. smogrank.com/rankings?w=30d&by=days. Ranked on low-cost sensors, with no reference monitor in the city: #1 Peshawar, #2 Multan, #5 Kasur, #7 Gujranwala, #8 Lahore, #9 Faisalabad and #10 Jammu. Some values from Sensor.Community, ODbL. Some readings from Vietnam's government monitors; Department of Environment, Nepal; Aurassure; RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver); Umhverfisstofnun (Environment Agency of Iceland), no reuse terms published.

Download top 10 by average (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.

Updated 2026-10-14 07:07 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: Vietnam's government monitors; Department of Environment, Nepal; Aurassure; RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver); Umhverfisstofnun (Environment Agency of Iceland), no reuse terms published (why we use them).