SmogRank / History / City race
Cities in Czechia, 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 Czechia for PM2.5 over the 30 days to 20 Oct 2023: Děčín 15.6 µg/m³, Ostrava 14.1 µg/m³ and Hradec Králové 14.0 µg/m³.
- 1DěčínÚstí nad Labem Region15.6
- 2OstravaMoravian-Silesian Region14.1
- 3Hradec KrálovéHradec Králové Region14.0
- 4OlomoucOlomouc Region13.8
- 5BerounCentral Bohemia13.8
- 6KladnoCentral Bohemia13.4
- 7MostÚstí nad Labem Region13.2
- 8BohumínMoravian-Silesian Region13.0
- 9KadaňÚstí nad Labem Region12.8
- 10ZnojmoSouth Moravian12.7
- 11Moravská TřebováPardubice Region12.7
- 12PřerovOlomouc Region12.6
- 13Český TěšínMoravian-Silesian Region12.5
- 14Mladá BoleslavCentral Bohemia12.4
- 15TepliceÚstí nad Labem Region12.3
- 16PraguePrague12.1
- 17OpavaMoravian-Silesian Region12.0
- 18StudénkaMoravian-Silesian Region11.9
- 19PardubicePardubice Region11.9
- 20ŽideniceSouth Moravian11.7
+ 16 more cities, 11.7 µg/m³ and below
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.