Air pollution is one of the leading causes of death around the world. Therefore you may be curious: where is the cleanest air in the world? And what city has the best air quality? Smart Air analyzed 2023 air pollution data from 493 major cities around the world to create the ranking of the “25 Cities with the Best Air Quality” to help you find the cities with the cleanest, safest air in the world.

Rankings: 25 Cities with the Best Air Quality

The rankings for best air quality in the world are based on PM2.5 air pollution data from the 12 months before the publication date.

WATCH: Top 5 Least Polluted Cities in 2022

Read on for the full list of 25 cities with the best air quality in the world and an analysis of what this data means.

1. Zürich, Switzerland (0.4 µg/m3)

2. Perth, Australia (1.5 µg/m3)

3. Hobart, Australia (2.3 µg/m3)

4. Uppsala, Sweden (3.5 µg/m3)

5. Launceston, Australia (3.5 µg/m3)

6. Reykjavík, Iceland (4.0 µg/m3)

7. Tampere, Finland (4.0 µg/m3)

8. Turku, Finland (4.1 µg/m3)

9. Vancouver, Canada (4.3 µg/m3)

10. Wollongong, Australia (4.4 µg/m3)

11. Honolulu, United States (4.5 µg/m3)

12. Albuquerque, United States (4.5 µg/m3)

13. Surrey, Canada (4.6 µg/m3)

14. Saint-Denis, Réunion (4.6 µg/m3)

15. Adelaide, Australia (4.7 µg/m3)

16. Edinburgh, Great Britain (4.7 µg/m3)

17. Tallinn, Estonia (4.7 µg/m3)

18. Stockholm, Sweden (4.7 µg/m3)

19. Trondheim, Norway (4.8 µg/m3)

20. Funchal, Portugal (4.8 µg/m3)

21. Sydney, Australia (4.9 µg/m3)

22. Bergen, Norway (4.9 µg/m3)

23. Salamanca, Estonia (4.9 µg/m3)

24. Halifax, Canada (4.9 µg/m3)

25. Portland, United States (5.0 µg/m3)

What is the Least Polluted City in the World?

Australia topped the list as the least polluted country in the world, with 6 cities in the top 25. Of the 25 least polluted cities in the world with the best air quality, Nordic countries (Finland, Sweden, Norway, Iceland) dominated the rankings with some of the cleanest air in the world in 2023.

12 out of the 25 cities with the best and cleanest air were either in Nordic countries or Australia. Zürich, Switzerland once again ranked as the least polluted city in the world. Australia and the United States were the only countries having at least 3 cities ranking in the top 25 least polluted cities in the world.

There is research that even small amounts of pollution such as those typically present in these least polluted cities can have an impact on health.

Below is a pollution heat map from the WHO. WHO research shows that over 99% of people in the world are breathing unsafe air with high air pollution levels.

How Air Pollution Was Measured to Find Cities with the Cleanest Air in the World

The above rankings of the 2023 least polluted cities in the world were ranked based on their average PM_2.5 pollution levels from the 12 months before the publication date.

These small pollutants have a width of fewer than 2.5 µg and are considered to be one of the more dangerous pollutants due to their ability to enter deep into the lungs and bloodstream.

Open Data

The PM2.5 AQI 2023 world pollution data used for the rankings of the world’s worst polluted cities are openly available at https://aqicn.org/data-platform/covid19/.

How I Protect Myself

Smart Air is a certified B Corp committed to combating the myths big companies use to inflate the price of clean air. We are a social enterprise dedicated to raising awareness about such issues and providing cost-effective solutions so that more people can enjoy cleaner air.

Smart Air provides empirically backed, no-nonsense purifiers and masks, that remove the same particles as the big companies for a fraction of the cost. Only corporations benefit when clean air is a luxury.

For protection against air pollution, check out the Sqair!

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