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.

=2267ClaytonNorth Carolina, United States 0%0 of 23
=2267RaleighNorth Carolina, United States 0%0 of 30
=2267DyersburgTennessee, United States 0%0 of 30
=2267ClintonIowa, United States 0%0 of 30
=2267RockfordIllinois, United States 0%0 of 30
=2267LindenNew Jersey, United States 0%0 of 30
=2267SteubenvilleOhio, United States 0%0 of 30
=2267PittsburghPennsylvania, United States 0%0 of 30
=2267Flagstafflast full day 11 OctArizona, United States 0%0 of 28
=2267Cedar Hillslast full day 11 OctUtah, United States 0%0 of 21
=2267Salt Lake CityUtah, United States 0%0 of 30
=2267Airway HeightsWashington, United States 0%0 of 30
=2267ToppenishWashington, United States 0%0 of 30
=2267Strawberry HillBritish Columbia, Canada 0%0 of 30
=2267Val-de-ReuilNormandy, France 0%0 of 30
=2267MorouraSaga, Japan 0%0 of 30
=2267NarashinoChiba, Japan 0%0 of 30
=2267ShirakawaFukushima, Japan 0%0 of 30
=2319Yasugichōlast full day 11 OctShimane, Japan 0%0 of 28
=2319MatsudoChiba, Japan 0%0 of 30
=2319Gōtsuchōlast full day 11 OctShimane, Japan 0%0 of 27
=2319FujinomiyaShizuoka, Japan 0%0 of 30
=2319MiuraKanagawa, Japan 0%0 of 30
=2319YotsukaidōChiba, Japan 0%0 of 27
=2319Thornaby-on-TeesEngland, United Kingdom 0%0 of 30
=2319NottinghamEngland, United Kingdom 0%0 of 30
=2319BrightlingseaEngland, United Kingdom 0%0 of 30
=2319BaselBasel-City, Switzerland 0%0 of 30
=2319Thalelast full day 10 OctSaxony-Anhalt, Germany 0%0 of 27
=2319Nordhausenlast full day 10 OctThuringia, Germany 0%0 of 26
=2319Lüdenscheidlast full day 10 OctNorth Rhine-Westphalia, Germany 0%0 of 27
=2319Kelsterbachlast full day 10 OctHesse, Germany 0%0 of 26
=2319FuldaHesse, Germany 0%0 of 29
=2319Villefranche-sur-SaôneAuvergne-Rhône-Alpes, France 0%0 of 30
=2319ValenceAuvergne-Rhône-Alpes, France 0%0 of 30
=2319OrléansCentre-Val de Loire, France 0%0 of 30
=2319Mont-de-MarsanNew Aquitaine, France 0%0 of 26
=2319MontbéliardBourgogne-Franche-Comté, France 0%0 of 30
=2319DoleBourgogne-Franche-Comté, France 0%0 of 30
=2319Bourg-en-BresseAuvergne-Rhône-Alpes, France 0%0 of 30
=2319GyöngyösHeves County, Hungary 0%0 of 29
=2319CookevilleTennessee, United States 0%0 of 30
=2319DavenportIowa, United States 0%0 of 30
=2319Iowa CityIowa, United States 0%0 of 30
=2319MuscatineIowa, United States 0%0 of 30
=2319East ChicagoIndiana, United States 0%0 of 28
=2319RochesterMinnesota, United States 0%0 of 30
=2319ChicoCalifornia, United States 0%0 of 30
=2319Bozemanlast full day 10 OctMontana, United States 0%0 of 26
=2319Stansbury parkUtah, United States 0%0 of 30
=2319BremertonWashington, United States 0%0 of 30
=2319BadgerAlaska, United States 0%0 of 30
=2319AirdrieAlberta, Canada 0%0 of 30
=2319KitimatBritish Columbia, Canada 0%0 of 29
=2319SquamishBritish Columbia, Canada 0%0 of 29
=2319Kennedy TownshipPennsylvania, United States 0%0 of 30
=2357SvishtovVeliko Tarnovo, Bulgaria 0%0 of 30
=2357NanaoIshikawa, Japan 0%0 of 30
=2357KanazawaIshikawa, Japan 0%0 of 30
=2357GotembaShizuoka, Japan 0%0 of 28
=2357FujiedaShizuoka, Japan 0%0 of 30
=2357OmigawaChiba, Japan 0%0 of 30
=2357ŌamiChiba, Japan 0%0 of 29
=2357NarrabriNew South Wales, Australia 0%0 of 30
=2357GunnedahNew South Wales, Australia 0%0 of 29
=2357EmeraldQueensland, Australia 0%0 of 30
=2357CacémLisbon, Portugal 0%0 of 30
=2357WakefieldEngland, United Kingdom 0%0 of 30
=2357Storringtonlast full day 11 OctEngland, United Kingdom 0%0 of 21
=2357ReutteTyrol, Austria 0%0 of 30
=2357NamurWallonia, Belgium 0%0 of 30
=2357Habay-la-VieilleWallonia, Belgium 0%0 of 29
=2357Oberviechtachlast full day 10 OctBavaria, Germany 0%0 of 27
=2357MichelstadtHesse, Germany 0%0 of 29
=2357HeidelbergBaden-Wurttemberg, Germany 0%0 of 30
=2357Hanau am MainHesse, Germany 0%0 of 29
=2357DarmstadtHesse, Germany 0%0 of 29
=2357GalwayConnacht, Ireland 0%0 of 30
=2357Saint-ÉtienneAuvergne-Rhône-Alpes, France 0%0 of 30
=2357PerpignanOccitanie, France 0%0 of 30
=2357CherbourgNormandy, France 0%0 of 30
=2357ChartresCentre-Val de Loire, France 0%0 of 30
=2357AlbiOccitanie, France 0%0 of 30
=2357Banská BystricaBanská Bystrica Region, Slovakia 0%0 of 28
=2357CarralGalicia, Spain 0%0 of 30
=2357RijekaPrimorje-Gorski Kotar, Croatia 0%0 of 30
=2357RiedstadtHesse, Germany 0%0 of 29
=2357JacksonvilleFlorida, United States 0%0 of 30
=2357Highland HeightsKentucky, United States 0%0 of 30
=2357DentOhio, United States 0%0 of 30
=2357SharonvilleOhio, United States 0%0 of 30
=2357JolietIllinois, United States 0%0 of 30
=2357Grand RapidsMichigan, United States 0%0 of 30
=2357LansingMichigan, United States 0%0 of 30
=2357Lincoln ParkMichigan, United States 0%0 of 30
=2357MinneapolisMinnesota, United States 0%0 of 30
=2357LincolnNebraska, United States 0%0 of 27
=2357ElizabethNew Jersey, United States 0%0 of 27
=2357Jefferson HillsPennsylvania, United States 0%0 of 30
=2357New HollandPennsylvania, 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).