Air pollution causes health problems and strains a country's healthcare system. IQAir's 8th annual report analyzed PM2.5 data from 9,446 cities in 143 countries and found Pakistan to be the country with the worst air quality in 2025.
Pakistan topped the list with 67.3 µg/m³ pollution followed by Bangladesh (66.1 µg/m³), Tajikistan (57.3 µg/m³), Chad (53.6 µg/m³) and the Democratic Republic of Congo (50.2 µg/m³). The worrying statistic is that 130 out of 143 countries (91%) exceeded WHO guidelines.
In the Southeast Asian region, the countries with the worst air pollution are Indonesia (30 µg/m³), Vietnam (29.7 µg/m³), Laos (22.6 µg/m³), Philippines (19 µg/m³), Cambodia (18.1 µg/m³), Thailand (17.8 µg/m³), Malaysia (16 µg/m³), and Singapore (11.9 µg/m³).
While Pakistan is the country with the worst air quality, the city with the worst air pollution is Loni, India with 112.5 µg/m³ while the city with the best air quality is Nieuwoudtville, South Africa 1.0 µg/m³. The 25 most polluted cities in the world are all located in India, Pakistan, and China.
Overall, Malaysia ranks 60th with Kuala Lumpur at 55th on the list of the world's worst air quality.
