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 27 Jul 2023: Čaňa 16.6 µg/m³, Trnava 15.7 µg/m³ and Prešov 15.4 µg/m³.
- 1ČaňaKošice Region16.6
- 2TrnavaTrnava Region15.7
- 3PrešovPrešov Region15.4
- 4KošiceKošice Region14.3
- 5NitraNitra Region13.5
- 6MartinŽilina Region13.2
- 7SmižanyKošice Region12.7
- 8Spišská Nová VesKošice Region12.6
- 9BratislavaBratislava Region12.3
- 10HumennéPrešov Region12.2
- 11SenicaTrnava Region11.9
- 12ŽilinaŽilina Region11.3
- 13Vranov nad TopľouPrešov Region11.2
- 14KolárovoNitra Region11.1
- 15RužomberokŽilina Region10.8
- 16PartizánskeTrenčín Region10.7
- 17ZvolenBanská Bystrica Region10.5
- 18Žiar nad HronomBanská Bystrica Region10.5
- 19PrievidzaTrenčín Region10.0
- 20Veľká LomnicaPrešov Region9.7
+ 7 more cities, the next at 9.7 µg/m³
Days missing from the source archive fall in this window, so fewer countries are counted.
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 reader for China's network. Turkey's network doesn't answer requests from outside the country, so we can't read it. Most cities there are missing from this board, not clean. Why.