Delhi tops list of most polluted megacities in 2025

India Dec 31, 2025

Delhi has been ranked the most polluted megacity in India for 2025, according to a new CREA report.
The city's PM2.5 levels hit an annual average of 96 ug/m3—more than double Kolkata's and nearly triple Mumbai's—far above both national and global safety standards.

Where is all this pollution coming from?

About 35% of Delhi's PM2.5 pollution comes from within the city, with vehicles leading at 46% of local emissions, followed by industries and households.
The rest—65%—drifts in from other NCR districts and beyond.

What does this mean for daily life?

Delhi's air quality index (AQI) remained concerning throughout the year, and there wasn't a single "Good" air day all year.
Most days were labeled "Poor," "Unhealthy," or even worse—a tough reality for anyone living or studying in the city.