SmogRank / History / City race
Cities in Slovakia, worst air first, day by day
Each measured city's average over the 30 days to every day since January 2023, worst first. Find your own city to follow it through the race, or keep to one country.
The worst cities in Slovakia for PM2.5 over the 30 days to 6 Sep 2026: Čaňa 15.9 µg/m³, Trebišov 11.4 µg/m³ and Humenné 11.1 µg/m³.
- 1ČaňaKošice Region15.9
- 2TrebišovKošice Region11.4
- 3HumennéPrešov Region11.1
- 4Vranov nad TopľouPrešov Region10.3
- 5KošiceKošice Region10.2
- 6PrešovPrešov Region10.1
- 7SenecBratislava Region10.0
- 8KrompachyKošice Region9.7
- 9SninaPrešov Region9.4
- 10TrnavaTrnava Region9.4
- 11NitraNitra Region9.4
- 12KomárnoNitra Region9.3
- 13PúchovTrenčín Region9.2
- 14BardejovPrešov Region8.7
- 15TrenčínTrenčín Region8.6
- 16PezinokBratislava Region8.6
- 17SenicaTrnava Region8.5
- 18PrievidzaTrenčín Region8.5
- 19Chorvátsky Grob - Čierna VodaBratislava Region8.5
- 20RužomberokŽilina Region8.4
+ 21 more cities, 8.4 µg/m³ and below
Not counted on this day, too few days measured: Handlová since 6 Sep 2026.
Cities counted each day
A city's number is its average over the 30 days, shown only when 21 of them were measured (5 of 7 on the 7-day race), the same minimum as the 30- and 7-day boards. A city whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.
Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites; we are building the readers for them. Most cities there are missing from this board, not clean. Why.