City air quality sees measurable improvement in 2025, says data

Delhi recorded a clear and measurable improvement in air quality in 2025, with cleaner air reported in a majority of months compared to 2024, according to a comparative analysis of Air Quality Index data available up to 9 December, 2025. The findings show fewer severe pollution days, more satisfactory air quality days and better conditions even during the critical winter months.

The analysis indicates that 2025 has seen the highest number of “Satisfactory” air quality days in the last nine years, excluding the pandemic year of 2020. This marks a significant shift for the national capital, which traditionally struggles with hazardous pollution levels, especially from October to February.

During the winter period of October to February, the number of satisfactory air quality days recorded so far in 2025-26 has already surpassed those seen during the same period in 2024-25. This improvement is significant because winter months usually witness a sharp spike in pollution due to weather conditions, stubble burning, vehicular emissions and dust.

Month-wise data from January to November shows that air quality was better in 8 out of 11 months in 2025 compared to the corresponding months in 2024. Average AQI levels improved in January, February, March, May, June, July, October and November. In one month, air quality remained at the same level as the previous year, while only two months recorded poorer conditions.

Category-wise analysis further highlights the positive trend. From January to November, the number of “Satisfactory” days rose from 66 in 2024 to 79 in 2025. At the same time, days under the “Moderate” category declined, while a sharp reduction was recorded in the “Very Poor” and “Severe” categories.

The most notable change was seen in the “Severe” category. In 2024, Delhi recorded 11 severe air pollution days. This number dropped to just three days in 2025. This reduction is considered crucial for public health, as severe air quality levels pose serious risks to children, elderly people and those with respiratory illnesses.

While the overall number of days falling under broader clean-air and polluted-air groupings remained similar in both years, the quality within these groups improved in 2025. This indicates that even when pollution was present, its intensity was lower than in the previous year.

October and November, typically the worst months for Delhi’s air, showed marked improvement. In October 2025, the average AQI was 11 points lower than in October 2024. Unlike 2024, which recorded no satisfactory days in October, the city saw four satisfactory air quality days in October 2025.

November showed an even stronger improvement. The average AQI in November 2025 was 20 points better than in November 2024. Severe pollution days dropped from eight in November 2024 to just three in November 2025. Only three days fell under the “Poor” category, compared to the previous year when AQI levels stayed above 300 throughout the month, mostly in the “Very Poor” or “Severe” range.

Air pollution hotspots across the city also reflected this improvement. Delhi has 13 identified pollution hotspots. In October 2025, nine of these hotspots recorded better average AQI levels than in October 2024, while one remained unchanged. In November 2025, all 13 hotspots showed improvement compared to the previous year.

Officials attribute the improvement to coordinated action by multiple departments, strict enforcement of winter action plans, control of dust, improved waste management, regulation of construction activity and increased use of pollution-control measures.