650 cities by people breathing unhealthy air, 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.

About 98.8M people in these 650 cities breathed unhealthy air on an average day over the last 30 days.

Ranked by people: each city's population times its share of unhealthy days, those with a daily mean over 35.4 µg/m³ (US AQI 101+). That is how many people living there breathed unhealthy air on an average day. Only cities measured at 2 or more places at least 3 km apart are ranked: one monitor shouldn't speak for a whole city. Population is the city itself, not its wider metro area.

201Hwaseong-siGyeonggi-do, South Korea 0
=202Mueang NonthaburiNonthaburi, Thailand 0
=202SejongSejong-si, South Korea 0
204New Taipei CityTaipei, Taiwan 0
=205Uijeongbu-siGyeonggi-do, South Korea 0
=205GwangjuGwangju, South Korea 0
=205ChungjuNorth Chungcheong, South Korea 0
=205PoznańGreater Poland, Poland 0
=209PraguePrague, Czechia 0
=209ToruńKujawsko-Pomorskie, Poland 0
=211WŏnjuGangwon-do, South Korea 0
=211SeosanChungcheongnam-do, South Korea 0
=211SinhyeonGyeongsangnam-do, South Korea 0
=211HanamGyeonggi-do, South Korea 0
=211KrakówLesser Poland, Poland 0
216Iaşilast full day 10 OctIași County, Romania 0
=217DaejeonDaejeon, South Korea 0
=217Celayalast full day 11 OctGuanajuato, Mexico 0
=219HonmachiKumamoto, Japan 0
=219São PauloSão Paulo, Brazil 0
=219Little RockArkansas, United States 0
222Taesal-liChungcheongnam-do, South Korea 0
=223SintansinDaejeon, South Korea 0
=223KwangyangJeollanam-do, South Korea 0
=223PłockMazovia, Poland 0
=223León de los AldamaGuanajuato, Mexico 0
227Voluntarilast full day 10 OctIlfov, Romania 0
=228DaeguDaegu, South Korea 0
=228Gyeongsan-siGyeongsangbuk-do, South Korea 0
=228GwangjuGyeonggi-do, South Korea 0
=228DakarDakar, Senegal 0
=228ZapopanJalisco, Mexico 0
=233BiałystokPodlasie, Poland 0
=233GimcheonGyeongsangbuk-do, South Korea 0
=233NamyangjuGyeonggi-do, South Korea 0
=233Leccolast full day 11 OctLombardy, Italy 0
=237WarsawMazovia, Poland 0
=237GongjuChungcheongnam-do, South Korea 0
=237HayangGyeongsangbuk-do, South Korea 0
=237JungpyongNorth Chungcheong, South Korea 0
=237Ciudad General EscobedoNuevo León, Mexico 0
=237KotōKumamoto, Japan 0
=243Bucharestlast full day 10 OctBucharest, Romania 0
=243ImsilJeollabuk-do, South Korea 0
=243ChangwonGyeongsangnam-do, South Korea 0
=243ChangsuJeollabuk-do, South Korea 0
=243MiyakonojōMiyazaki, Japan 0
=243MaconGeorgia, United States 0
=243MercedCalifornia, United States 0
=250CandelariaCanary Islands, Spain 0
=250Berlinlast full day 11 OctState of Berlin, Germany 0
=250BakersfieldCalifornia, United States 0
=253Seongnam-siGyeonggi-do, South Korea 0
=253ComptonCalifornia, United States 0
=253Los AngelesCalifornia, United States 0
=256HumennéPrešov Region, Slovakia 0
=256YeongjuGyeongsangbuk-do, South Korea 0
=256ZnojmoSouth Moravian, Czechia 0
=259NaesŏGyeongsangnam-do, South Korea 0
=259NiceProvence-Alpes-Côte d'Azur, France 0
=261YangsanGyeongsangnam-do, South Korea 0
=261YeosuJeollanam-do, South Korea 0
=261MonterreyNuevo León, Mexico 0
=264KošiceKošice Region, Slovakia 0
=264OkazakiAichi, Japan 0
=264KumamotoKumamoto, Japan 0
=264Wake ForestNorth Carolina, United States 0
=264MiddletownOhio, United States 0
=269UlsanUlsan, South Korea 0
=269BusanBusan, South Korea 0
=269Ústí nad LabemÚstí nad Labem Region, Czechia 0
=269GdańskPomerania, Poland 0
=269CasertaCampania, Italy 0
274SendaiKagoshima, Japan 0
=275KariyaAichi, Japan 0
=275KagoshimaKagoshima, Japan 0
=275SaijōEhime, Japan 0
=275RoubaixHauts-de-France, France 0
=275BilbaoBasque Country, Spain 0
=275Cape Townlast full day 8 OctWestern Cape, South Africa 0
=281Cluj-Napocalast full day 10 OctCluj County, Romania 0
=281Flémalle-HauteWallonia, Belgium 0
=281NitraNitra Region, Slovakia 0
=281San JoseCalifornia, United States 0
=281TōkaiAichi, Japan 0
=286FukuyamaHiroshima, Japan 0
=286Augsburglast full day 10 OctBavaria, Germany 0
=286LjubljanaLjubljana, Slovenia 0
=286CarsonCalifornia, United States 0
290NaplesCampania, Italy 0
=291Yangp'yŏngGyeonggi-do, South Korea 0
=291KimhaeGyeongsangnam-do, South Korea 0
=291GwangyangJeollanam-do, South Korea 0
=291SzczecinWest Pomerania, Poland 0
=291MadridMadrid, Spain 0
=296GijangBusan, South Korea 0
=296ChinjuGyeongsangnam-do, South Korea 0
=296UngsangGyeongsangnam-do, South Korea 0
=296CampinasSão Paulo, Brazil 0
=296InglewoodCalifornia, United States 0

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 people breathing unhealthy air (PM2.5), last 30 days to 14 Oct 2026, 07:00 UTC: each city's population times its share of measured days with a daily mean over 35.4 µg/m³ (only cities with 2 or more monitoring places 3 km or more apart), 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=people. Ranked on low-cost sensors, with no reference monitor in the city: #1 Lahore, #2 Dhaka, #4 Peshawar, #8 Faisalabad and #10 Rawalpindi. Some values from Sensor.Community, ODbL. Some readings from Vietnam's government monitors; Aurassure; Department of Environment, Nepal; 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; Aurassure; Department of Environment, Nepal; 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).