Interactive global map of 2025 PM2.5 concentrations by city

About this report

The 2025 IQAir World Air Quality Report provides a comprehensive overview of air quality across the globe for the calendar year 2025. This Report presents PM2.5 air quality data sourced from 9,446 cities spanning 143 countries, regions, and territories. The information is sourced from more than 40,000 regulatory monitoring stations and low-cost sensors, managed by a wide array of contributors, including government agencies, universities, non-profit organizations, private enterprises, and engaged citizen scientists around the world.

PM2.5 concentrations are reported in micrograms per cubic meter (μg/m³), following the World Health Organization (WHO) annual PM2.5 air quality guideline and interim targets. This standardized approach supports effective data visualization and clear risk communication. The air quality metrics featured in this Report are derived from IQAir’s real-time monitoring platform, which systematically validates, calibrates, and harmonizes data from monitoring stations worldwide.

To explore historical air quality trends by city, country, and region, the IQAir website features an interactive map showcasing annual city concentrations and global air quality rankings for the 9,446 cities included in the Report. IQAir is committed to fostering engagement, knowledge-sharing, and collective action among governments, educators, researchers, non-profits, businesses, and the public to promote air quality awareness. Our mission is to enable informed discussions and drive actions that improve air quality and protect the well-being of communities globally.

Executive Summary

While air pollution has long been recognized as a persistent hazard, 2025 marked a turning point as international institutions finally elevated the crisis to the forefront of the global agenda. This shift was underscored by the 2025 World Economic Forum Global Risks Report, which, for the first time, dedicated a specific section to air pollutants and ranked the issue as a top-tier global risk.^1,2 Alongside these economic warnings, the United Nations General Assembly formally categorized air pollution as a major risk factor for non-communicable diseases, including cardiac disease, stroke, and cancer.³ To operationalize these goals, the World Health Assembly has approved a landmark roadmap to halve deaths from air pollution by 2040.⁴

However, translating this global consensus into measurable impact remains a challenge as environmental volatility increases. Wildfires, bolstered by climate change, played a primary role in degrading global air quality in 2025. Record emissions from Europe and Canada contributed to a global release of approximately 1,380 megatonnes of carbon from biomass burning.⁵

Last year’s World Air Quality Report incorporated data from 8,954 cities in 138 countries, regions, and territories. The current Report expanded to cover 9,446 cities in 143 countries, regions, and territories. An increase in 2025 data contributions from West Asia, notably the inclusion of Iran, Syria, and Jordan, resulted in a 33% increase in the number of cities covered. While this region remains the least represented and has been historically undermonitored, this growth marks a critical step toward closing global data gaps. Notably, Burundi, Turkmenistan, and Togo—all of which ranked among the top 30 most polluted countries in 2024—are absent from this year’s Report due to a lack of available data.

Globally, just 13 countries, regions, and territories saw annual average PM2.5 concentrations meeting the WHO annual PM2.5 guideline of 5 μg/m³, with the majority located in the Latin America and Caribbean region. Yet, the 2025 data serves as a critical reminder that air quality is not a static achievement, but a fragile asset. In 2025, wildfire activity severely impacted regions that have historically experienced relatively low PM2.5 levels. As a result, only 14% of global cities met the WHO annual PM2.5 guideline in 2025, compared to 17% in 2024. This downward trend serves as a stark reminder that maintaining clean air requires active stewardship and a proactive strategy—regardless of historical performance. Maintaining clean air is a long-term commitment to incremental improvement rather than a single policy goal achieved or annual target concentration reached. For children, however, the impact of air pollution exposure can last a lifetime; the respiratory damage sustained during developmental years is often irreversible. As the demographic with the least agency in these environmental shifts, children are left to bear the permanent health costs of air quality they did not choose.

References

[1] Elsner M. These are the biggest risks we face now and in the next 10 years. World Economic Forum. Published January 15, 2025. https://www.weforum.org/stories/2025/01/global-risks-report-2025-bleak-predictions/

[2] Clean Air Fund. Air quality news January 2025. Published January 15, 2025. https://www.cleanairfund.org/news-item/roundup-january-2025/

[3] United Nations General Assembly. Political declaration of the fourth high-level meeting of the General Assembly on the prevention and control of noncommunicable diseases and the promotion of mental health and well-being. Published December 8, 2025. https://docs.un.org/en/A/80/L.34

[4] Renshaw N. World Health Assembly approves roadmap to halve deaths from air pollution. Published May 28, 2025. https://www.cleanairfund.org/news-item/wha-approves-roadmap/

[5] Copernicus. 2025 sees intense wildfire year in the Northern Hemisphere. Published December 3, 2025. https://atmosphere.copernicus.eu/2025-sees-intense-wildfire-year-northern-hemisphere