New Delhi: Delhi’s air quality showed a marked improvement in 2025, with the national capital recording the second-lowest annual average Air Quality Index (AQI) since 2018, barring the Covid year of 2020, data released by the Ministry of Environment, Forest and Climate Change showed.
The Commission for Air Quality Management in NCR and Adjoining Areas (CAQM) said sustained policy interventions and year-round field-level actions helped the city log 79 days with AQI at 100 or below—classified as ‘Good’ and ‘Satisfactory’—the highest such count since 2020. The number of ‘Severe’ to ‘Severe+’ AQI days fell to just eight in 2025, the second-lowest since 2018.
On an annual basis, Delhi’s average AQI stood at 201 in 2025, improving from 209 in 2024 and 204 in 2023, and significantly lower than levels seen in earlier years such as 2018 (225) and 2019 (215). Officials noted that despite an unusually high average AQI of 351 in December due to unfavourable meteorological conditions and low wind speeds, the overall annual performance remained the strongest in seven years.
Month-wise data showed February and July 2025 recorded the lowest-ever average AQI for those months since 2018, even outperforming the Covid year. January, May and June also posted their second-best air quality levels in the same period.
Particulate matter concentrations also declined. The daily average PM2.5 level in 2025 was 96 micrograms per cubic metre, while PM10 stood at 197 micrograms per cubic metre—both the lowest readings since 2018, excluding 2020. In comparison, PM2.5 levels were above 100 micrograms per cubic metre in most years prior to 2023, reflecting the scale of improvement.
The data further showed an increase in days categorised as ‘Good to Moderate’ (AQI below 200), which rose to 200 in 2025 from 209 in 2024, while ‘Severe to Severe+’ days dropped sharply compared to 17 days in 2024 and 15 days in 2023.
Officials said continued implementation of targeted policy measures across transport, industry, construction and waste management is expected to deliver gradual but sustained improvements in Delhi’s air quality in the coming years.