Pakistan ranked most polluted country in 2025, shows Swiss air quality report

India’s particulate matter (PM2.5) concentrations were at a three-year low, though it still is the sixth most polluted country in the world, according to the World Air Quality Report, a yearly global compilation of air quality by IQAir, a Swiss company that makes air filtration devices.

India’s population-weighted annual average PM2.5 concentration in 2025 was 48.9 µg/m³, a 3% decrease from 2024 (50.6 µg/m³) and a 10% decrease from 2023 (54.4 µg/m³). The 2025 numbers were part of a report—now in its eighth edition—made public on Tuesday (March 24, 2026).

The population-weighted numbers that IQAir calculates give more weight to the particulate matter numbers from cities with higher population—a metric meant to underline the quality of air that the majority of a country’s population are exposed to.