Delhi recorded its cleanest July air since 2018 in July 2025, with an average Air Quality Index (AQI) of 78- firmly in the 'Satisfactory' category. This achievement surpasses even the air recorded during the COVID-19 lockdown in the year 2020, marking a significant milestone in the city's battle against air pollution.
Best July AQI in years: Data behind the progress
The average AQI for July 2025 was 78, which is not only an improvement from recent years but also better than the lockdown year of 2020. For context, previous Julys recorded much worse air quality: 104 (2018), 134 (2019), 84 (2020), 110 (2021), 87 (2022), 84 (2023), and 96 (2024).
Furthermore, July 2025 saw the highest number of ‘Satisfactory’ air days ever for this month, 29 days, compared to 16 in 2018 and as few as 12 in 2019. Even compared to other positive years, such as 2020 and 2022, July 2025 exceeded its count of 25 'Satisfactory' days.
January to July 2025: No severe pollution, improved particulate matter
From January through July 2025, Delhi maintained an average AQI of 184, an improvement over recent years (204 in 2024, 183 in 2023, 209 in 2022, 205 in 2021). Notably, during this period, there were no days classified in the “Severe” or “Severe+” categories (AQI over 400)- a stark contrast to earlier years, when up to seven such days would occur before August.
The same period saw reductions in both PM2.5 and PM10, the two most harmful particulate pollutants in Delhi’s air. The running average for PM2.5 was 79 µg/m³, the lowest since 2018 except for the anomalies of 2020, and PM10 dropped to an average of 180 µg/m³.
What drove the improvement?
The improvement is credited to a combination of favourable meteorological conditions, particularly ample and well-distributed rainfall throughout July, and coordinated multi-stakeholder action. Officials and experts point to “Delhi’s multi-agency implementation model, continuous landfill action, intensified sweeping operations, and a clear commitment to outcome-based governance” as crucial factors.
The Commission for Air Quality Management (CAQM) and the Delhi government have also increased efforts, with measures like pilot projects to test outdoor air purifiers in public spaces such as Nehru Park, aiming for localised “clean air zones” in areas with high public footfall.
Outlook and ongoing initiatives
Authorities state that efforts will be stepped up further in upcoming months. The air quality improvements seen so far make 2025 stand out as a potential record-setting year for clean air in Delhi, excluding exceptional situations such as the COVID-19 lockdown year.
Delhi Environment Minister Manjinder Singh Sirsa recently emphasised ongoing studies and pilot interventions, reiterating the city’s commitment to further lowering AQI, particularly in spaces frequented for recreation and exercise.
Delhi’s experience in July 2025 demonstrates that targeted pollution control, favourable weather, and coordinated governance can substantially improve urban air quality, even in one of the world’s most polluted megacities.