LIVE • 2026-05-27
Highest NO2 cities right now
Top 30 cities ranked by current NO2 concentration across all 217 tracked locations. Refreshes every 30 minutes. The highest NO2 right now is in Santiago, Chile at 121.2 ppb. WHO 2021 annual guideline: 10 μg/m³ (~5 ppb).
About NO2
See the full NO2 guide for sources, health effects, and mitigation. Or jump back to overall most polluted cities ranked by US EPA Air Quality Index.
See also: highest PM2.5 · highest PM10 · highest O3