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.

=2880BothellWashington, United States 0%0 of 30
=2880North BendWashington, United States 0%0 of 30
=2880RidgefieldWashington, United States 0%0 of 30
=2880Spokane ValleyWashington, United States 0%0 of 30
=2880MontréalQuebec, Canada 0%0 of 30
=2880St. CatharinesOntario, Canada 0%0 of 30
=2880QuébecQuebec, Canada 0%0 of 30
=2908HelsinkiUusimaa, Finland 0%0 of 30
=2908Gorna OryahovitsaVeliko Tarnovo, Bulgaria 0%0 of 29
=2908SakuNagano, Japan 0%0 of 30
=2908GoulburnNew South Wales, Australia 0%0 of 29
=2908Royal Leamington SpaEngland, United Kingdom 0%0 of 30
=2908IrlamEngland, United Kingdom 0%0 of 30
=2908DunholmeEngland, United Kingdom 0%0 of 30
=2908CreweEngland, United Kingdom 0%0 of 30
=2908AylesburyEngland, United Kingdom 0%0 of 30
=2908AndoverEngland, United Kingdom 0%0 of 30
=2908Tarplast full day 10 OctSchleswig-Holstein, Germany 0%0 of 26
=2908LeixlipLeinster, Ireland 0%0 of 30
=2908Dún LaoghaireLeinster, Ireland 0%0 of 29
=2908BlanchardstownLeinster, Ireland 0%0 of 30
=2908RevinGrand Est, France 0%0 of 30
=2908NiortNew Aquitaine, France 0%0 of 30
=2908NeversBourgogne-Franche-Comté, France 0%0 of 30
=2908MontluçonAuvergne-Rhône-Alpes, France 0%0 of 30
=2908LourdesOccitanie, France 0%0 of 30
=2908ClaymontDelaware, United States 0%0 of 28
=2908SeafordDelaware, United States 0%0 of 30
=2908DavieFlorida, United States 0%0 of 30
=2908East LakeFlorida, United States 0%0 of 30
=2908WellingtonFlorida, United States 0%0 of 30
=2908AshburnVirginia, United States 0%0 of 30
=2908WaterburyConnecticut, United States 0%0 of 30
=2908SpringfieldMassachusetts, United States 0%0 of 30
=2908BrainerdMinnesota, United States 0%0 of 30
=2908AllentownPennsylvania, United States 0%0 of 30
=2908AppletonWisconsin, United States 0%0 of 30
=2908TomahWisconsin, United States 0%0 of 28
=2908OjaiCalifornia, United States 0%0 of 30
=2908Apache JunctionArizona, United States 0%0 of 27
=2908WindsorColorado, United States 0%0 of 28
=2908BoiseIdaho, United States 0%0 of 30
=2908MoscowIdaho, United States 0%0 of 30
=2908MilwaukieOregon, United States 0%0 of 28
=2908TalentOregon, United States 0%0 of 30
=2908LongviewWashington, United States 0%0 of 30
=2908BramptonOntario, Canada 0%0 of 30
=2908BrossardQuebec, Canada 0%0 of 27
=2908OakvilleOntario, Canada 0%0 of 30
=2908WaterdownOntario, Canada 0%0 of 30
=2908Picnic Point-North LynnwoodWashington, United States 0%0 of 30
=2908West Vancouverlast full day 10 OctBritish Columbia, Canada 0%0 of 27
=2908HakubaNagano, Japan 0%0 of 27
=2954LaaksolahtiUusimaa, Finland 0%0 of 30
=2954AlmeríaAndalusia, Spain 0%0 of 30
=2954WorcesterEngland, United Kingdom 0%0 of 30
=2954SunderlandEngland, United Kingdom 0%0 of 30
=2954SeafordEngland, United Kingdom 0%0 of 30
=2954ChesterfieldEngland, United Kingdom 0%0 of 30
=2954ZierenbergHesse, Germany 0%0 of 29
=2954FürthHesse, Germany 0%0 of 29
=2954MallowMunster, Ireland 0%0 of 30
=2954TroyesGrand Est, France 0%0 of 26
=2954PanazolNew Aquitaine, France 0%0 of 24
=2954La RochelleNew Aquitaine, France 0%0 of 26
=2954FontainebleauÎle-de-France, France 0%0 of 30
=2954Cangas del Narcealast full day 11 OctAsturias, Spain 0%0 of 26
=2954Kennett SquarePennsylvania, United States 0%0 of 30
=2954CharlottesvilleVirginia, United States 0%0 of 28
=2954Rose HillVirginia, United States 0%0 of 30
=2954BrookingsSouth Dakota, United States 0%0 of 29
=2954GlendaleArizona, United States 0%0 of 30
=2954LakewoodColorado, United States 0%0 of 27
=2954ButteMontana, United States 0%0 of 30
=2954BeavertonOregon, United States 0%0 of 30
=2954Forest GroveOregon, United States 0%0 of 28
=2954Grants PassOregon, United States 0%0 of 30
=2954SilvertonOregon, United States 0%0 of 30
=2954North OgdenUtah, United States 0%0 of 30
=2954QuincyWashington, United States 0%0 of 30
=2954Walla WallaWashington, United States 0%0 of 28
=2954ChathamOntario, Canada 0%0 of 30
=2954Rivière-des-Prairies–Pointe-aux-TremblesQuebec, Canada 0%0 of 30
=2984VantaaUusimaa, Finland 0%0 of 30
=2984InaNagano, Japan 0%0 of 29
=2984SwindonEngland, United Kingdom 0%0 of 30
=2984ReadingEngland, United Kingdom 0%0 of 30
=2984CannockEngland, United Kingdom 0%0 of 30
=2984JumetWallonia, Belgium 0%0 of 30
=2984RoscommonConnacht, Ireland 0%0 of 30
=2984Clermont-FerrandAuvergne-Rhône-Alpes, France 0%0 of 30
=2984BloisCentre-Val de Loire, France 0%0 of 30
=2984Bellegarde-sur-ValserineAuvergne-Rhône-Alpes, France 0%0 of 30
=2984AngletNew Aquitaine, France 0%0 of 23
=2984NewarkDelaware, United States 0%0 of 30
=2984Winter ParkFlorida, United States 0%0 of 30
=2984Atlantic CityNew Jersey, United States 0%0 of 30
=2984South VinelandNew Jersey, United States 0%0 of 30
=2984Fall RiverMassachusetts, United States 0%0 of 30
=2984Detroit LakesMinnesota, United States 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).