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September 21, 2026

Global Air Quality Update - Week of September 21, 2026

Live data snapshot for September 21, 2026. 217 cities tracked. Global average AQI: 72.

This week's most polluted city is Riyadh, Saudi Arabia at AQI 1366. The cleanest air right now is in Quito, Ecuador at AQI 13.

Biggest changes this week

Worsening

Improving

Global average shifted from 67 to 72 (+5).

Top 10 most polluted cities right now

  1. Riyadh, Saudi Arabia - AQI 1366 (PM2.5 260.8 μg/m³)
  2. Kuwait City, Kuwait - AQI 462 (PM2.5 74.5 μg/m³)
  3. Bandung, Indonesia - AQI 184 (PM2.5 54.1 μg/m³)
  4. Guangzhou, China - AQI 180 (PM2.5 49.6 μg/m³)
  5. Faisalabad, Pakistan - AQI 180 (PM2.5 53.7 μg/m³)
  6. Hanoi, Vietnam - AQI 176 (PM2.5 55.6 μg/m³)
  7. Beijing, China - AQI 175 (PM2.5 42.4 μg/m³)
  8. Jakarta, Indonesia - AQI 171 (PM2.5 56.2 μg/m³)
  9. Lahore, Pakistan - AQI 165 (PM2.5 47.3 μg/m³)
  10. Delhi, India - AQI 164 (PM2.5 53.4 μg/m³)

Top 10 cleanest cities right now

  1. Quito, Ecuador - AQI 13 (PM2.5 3 μg/m³)
  2. Stockholm, Sweden - AQI 21 (PM2.5 1.3 μg/m³)
  3. Nur-Sultan, Kazakhstan - AQI 21 (PM2.5 2 μg/m³)
  4. Yangon, Myanmar - AQI 23 (PM2.5 3.7 μg/m³)
  5. Hua Hin, Thailand - AQI 23 (PM2.5 2.1 μg/m³)
  6. Tallinn, Estonia - AQI 24 (PM2.5 3.1 μg/m³)
  7. Belo Horizonte, Brazil - AQI 24 (PM2.5 5.3 μg/m³)
  8. Havana, Cuba - AQI 24 (PM2.5 2.6 μg/m³)
  9. La Paz, Bolivia - AQI 25 (PM2.5 8.7 μg/m³)
  10. San Jose, Costa Rica - AQI 25 (PM2.5 2 μg/m³)

What is AQI?

AQI (Air Quality Index) is a 0-500 scale used by the US EPA. Below 50 is good, above 150 unhealthy, above 300 hazardous. Most damage comes from PM2.5 - fine particles that enter the bloodstream. Learn more: PM2.5 explained.

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Data: live readings refreshed every 30 minutes by atmos.today. See methodology and attribution.