SmogRank / History / City race
Cities in Brazil, 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 Brazil for PM2.5 over the 30 days to 15 May 2026: Nilópolis 16.7 µg/m³, Ferraz de Vasconcelos 16.3 µg/m³ and São Paulo 15.9 µg/m³.
- 1NilópolisRio de Janeiro16.7
- 2Ferraz de VasconcelosSão Paulo16.3
- 3São PauloSão Paulo15.9
- 4LimeiraSão Paulo15.7
- 5JundiaíSão Paulo15.0
- 6CampinasSão Paulo15.0
- 7PaulíniaSão Paulo14.8
- 8Ribeirão PretoSão Paulo14.6
- 9São José do Rio PretoSão Paulo14.3
- 10TaubatéSão Paulo13.0
- 11PiracicabaSão Paulo12.6
- 12CubatãoSão Paulo12.4
- 13Duque de CaxiasRio de Janeiro12.1
- 14BauruSão Paulo12.1
- 15SantosSão Paulo12.0
- 16ItaguaíRio de Janeiro12.0
- 17GuaratinguetáSão Paulo11.9
- 18ItaquaquecetubaSão Paulo11.4
- 19São José dos CamposSão Paulo11.3
- 20AcariRio de Janeiro8.3
+ 2 more cities, the next at 8.0 µg/m³
Not counted on this day, too few days measured: Presidente Prudente since 11 May 2026 and Rio Claro since 10 May 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 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.