SmogRank / Countries / Switzerland / May 2025

Most polluted cities in Switzerland, May 2025

6 cities in Switzerland ranked by their average PM2.5 over the 31 days. Worst: Winterthur at 11.3 µg/m³, #358 of 2,193 cities in the world. Cleanest: Lugano at 4.4. A city needs measurements on 70% of the days to be ranked.

  1. 1Winterthurlow-cost sensorsZurich
    11.3
  2. 2ZürichZurich
    8.1
  3. 3BaselBasel-City
    7.0
  4. 4BernBern
    6.7
  5. 5BellinzonaTicino
    4.9
  6. 6LuganoTicino
    4.4
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+

All cities in the world, May 2025 · Switzerland now