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Cities With the Highest Ozone Right Now

Queens has the highest ground-level ozone concentration in our major-city sample right now, at about 168.0 µg/m³.

Updated hourly. Last updated Aug 9, 2026, 9:05:09 PM UTC.

Cities with at least 200,000 residents; 100 cities shown.

Top Cities Ranked by Ozone (O3)

# City Country US AQIPM2.5 Ozone (O3)
🥇 Queens United States 7321.1 µg/m³ 168.0 µg/m³
🥈 Haikou China 7119.8 µg/m³ 154.0 µg/m³
=3 Mexico City Mexico 6014.0 µg/m³ 145.0 µg/m³
=3 Ecatepec de Morelos Mexico 6014.0 µg/m³ 145.0 µg/m³
4 Chicago United States 6013.7 µg/m³ 131.0 µg/m³
=5 Philadelphia United States 5511.1 µg/m³ 129.0 µg/m³
=5 Zhanjiang China 6919.0 µg/m³ 129.0 µg/m³
6 Kuwait City Kuwait 17183.4 µg/m³ 128.0 µg/m³
7 The Bronx United States 478.5 µg/m³ 123.0 µg/m³
8 Santiago de Querétaro Mexico 5310.0 µg/m³ 120.0 µg/m³
9 Maoming China 7019.4 µg/m³ 119.0 µg/m³
10 Cixi China 5310.0 µg/m³ 118.0 µg/m³
11 Ningbo China 5611.8 µg/m³ 117.0 µg/m³
12 Ciudad Juárez Mexico 183.2 µg/m³ 116.0 µg/m³
=13 New York City United States 447.9 µg/m³ 114.0 µg/m³
=13 Brooklyn United States 447.9 µg/m³ 114.0 µg/m³
=13 Manhattan United States 447.9 µg/m³ 114.0 µg/m³
=13 Taizhou China 5611.6 µg/m³ 114.0 µg/m³
=14 Toronto Canada 5813.0 µg/m³ 113.0 µg/m³
=14 Kananga Democratic Republic of Congo 189109.4 µg/m³ 113.0 µg/m³
=15 Phoenix United States 6214.8 µg/m³ 112.0 µg/m³
=15 Dallas United States 407.2 µg/m³ 112.0 µg/m³
=16 Shaoxing China 5511.4 µg/m³ 111.0 µg/m³
=16 Iztapalapa Mexico 519.3 µg/m³ 111.0 µg/m³
17 Changde China 5511.0 µg/m³ 109.0 µg/m³
18 Los Angeles United States 7522.1 µg/m³ 108.0 µg/m³
19 Changsha China 5712.2 µg/m³ 107.0 µg/m³
=20 Zapopan Mexico 376.6 µg/m³ 106.0 µg/m³
=20 Baoji China 12043.3 µg/m³ 106.0 µg/m³
=20 Guadalajara Mexico 376.6 µg/m³ 106.0 µg/m³
=21 Hangzhou China 5712.3 µg/m³ 104.0 µg/m³
=21 Qingdao China 5913.2 µg/m³ 104.0 µg/m³
=21 Doha Qatar 15256.7 µg/m³ 104.0 µg/m³
=21 Yiyang China 5410.8 µg/m³ 104.0 µg/m³
22 Guankou China 5812.7 µg/m³ 102.0 µg/m³
=23 Al Başrah al Qadīmah Iraq 192114.3 µg/m³ 101.0 µg/m³
=23 Kaohsiung Taiwan 6315.4 µg/m³ 101.0 µg/m³
=23 Basrah Iraq 192114.3 µg/m³ 101.0 µg/m³
=24 Ganzhou China 6315.3 µg/m³ 100.0 µg/m³
=24 Milan Italy 5712.3 µg/m³ 100.0 µg/m³
25 Puebla Mexico 366.5 µg/m³ 98.0 µg/m³
=26 Singapore Singapore 8024.6 µg/m³ 97.0 µg/m³
=26 Singapore Singapore 8024.6 µg/m³ 97.0 µg/m³
=26 Nanyang China 5611.7 µg/m³ 97.0 µg/m³
=26 Dammam Saudi Arabia 15358.7 µg/m³ 97.0 µg/m³
=26 Xinyang China 6013.9 µg/m³ 97.0 µg/m³
=27 Kabul Afghanistan 8627.9 µg/m³ 96.0 µg/m³
=27 Brasilia Brazil 254.5 µg/m³ 96.0 µg/m³
=27 León de los Aldama Mexico 397.0 µg/m³ 96.0 µg/m³
28 Xiangyang China 5812.8 µg/m³ 95.0 µg/m³
=29 La Paz Bolivia 6013.9 µg/m³ 93.0 µg/m³
=29 Goiânia Brazil 295.3 µg/m³ 93.0 µg/m³
=29 San Diego United States 6516.6 µg/m³ 93.0 µg/m³
=30 Shanghai China 305.4 µg/m³ 92.0 µg/m³
=30 São Paulo Brazil 6516.7 µg/m³ 92.0 µg/m³
=30 Baku Azerbaijan 519.1 µg/m³ 92.0 µg/m³
=30 Xining China 7019.4 µg/m³ 92.0 µg/m³
=31 Houston United States 529.9 µg/m³ 90.0 µg/m³
=31 Lubumbashi Democratic Republic of Congo 13950.8 µg/m³ 90.0 µg/m³
=31 San Antonio United States 234.2 µg/m³ 90.0 µg/m³
32 Qinzhou China 6114.2 µg/m³ 89.0 µg/m³
=33 Aleppo Syria 529.7 µg/m³ 87.0 µg/m³
=33 Karbala Iraq 6617.4 µg/m³ 87.0 µg/m³
=34 Gaziantep Türkiye 6114.4 µg/m³ 86.0 µg/m³
=34 Liuzhou China 7120.0 µg/m³ 86.0 µg/m³
=35 Manaus Brazil 5812.6 µg/m³ 85.0 µg/m³
=35 Ordos China 5511.2 µg/m³ 85.0 µg/m³
=36 Montréal Canada 305.4 µg/m³ 84.0 µg/m³
=36 Yiwu China 91.6 µg/m³ 84.0 µg/m³
=37 Istanbul Türkiye 5511.5 µg/m³ 83.0 µg/m³
=37 Belo Horizonte Brazil 529.7 µg/m³ 83.0 µg/m³
=37 Prague Czechia 488.7 µg/m³ 83.0 µg/m³
38 Wenzhou China 407.2 µg/m³ 82.0 µg/m³
=39 Alexandria Egypt 6315.8 µg/m³ 81.0 µg/m³
=39 İzmir Türkiye 5913.2 µg/m³ 81.0 µg/m³
=39 Lianyungang China 498.8 µg/m³ 81.0 µg/m³
=39 Hamburg Germany 529.5 µg/m³ 81.0 µg/m³
=39 Chaozhou China 5511.1 µg/m³ 81.0 µg/m³
=39 Suqian China 407.2 µg/m³ 81.0 µg/m³
=40 Berlin Germany 468.3 µg/m³ 80.0 µg/m³
=40 Guayaquil Ecuador 5511.3 µg/m³ 80.0 µg/m³
=40 Jieyang China 5712.3 µg/m³ 80.0 µg/m³
=41 Lucknow India 8426.9 µg/m³ 79.0 µg/m³
=41 Tijuana Mexico 6416.2 µg/m³ 79.0 µg/m³
=41 Qingyuan China 7321.1 µg/m³ 79.0 µg/m³
=41 Multan Pakistan 15966.8 µg/m³ 79.0 µg/m³
=41 Xuchang China 5310.1 µg/m³ 79.0 µg/m³
=42 Lusaka Zambia 7421.5 µg/m³ 78.0 µg/m³
=42 Mbuji-Mayi Democratic Republic of Congo 15662.4 µg/m³ 78.0 µg/m³
=42 Medina Saudi Arabia 8326.3 µg/m³ 78.0 µg/m³
=43 Lima Peru 6415.9 µg/m³ 77.0 µg/m³
=43 London United Kingdom 346.2 µg/m³ 77.0 µg/m³
=43 Suzhou China 386.9 µg/m³ 77.0 µg/m³
=43 Kunshan China 386.9 µg/m³ 77.0 µg/m³
=43 Luohe China 5410.6 µg/m³ 77.0 µg/m³
=44 Algiers Algeria 7019.3 µg/m³ 76.0 µg/m³
=44 Santo Domingo Dominican Republic 6617.3 µg/m³ 76.0 µg/m³
=44 Bayan Nur China 6315.4 µg/m³ 76.0 µg/m³
=44 Yinchuan China 7019.5 µg/m³ 76.0 µg/m³
=44 Jinhua China 91.6 µg/m³ 76.0 µg/m³

Methodology: Current pollutant concentrations are sampled from WeatherAPI for up to 400 large cities; US AQI values are calculated from PM2.5 using EPA breakpoints.

Why Is Ground-Level Ozone So High in These Cities?

Ground-level ozone forms when sunlight drives reactions between pollutants from traffic, industry and other sources. Concentrations often peak on warm, sunny afternoons and can irritate the lungs even when particle pollution is modest.

Frequently Asked Questions: Cities With the Highest Ozone Right Now

Which city has the highest ozone right now?
Among the major cities we track, Queens has the highest current ozone concentration at about 168.0 µg/m³ (as of August 9, 2026).
Is ground-level ozone the same as the ozone layer?
It is the same molecule but in the wrong place: stratospheric ozone protects Earth, while ozone near the ground is a harmful air pollutant.