Most air polluted country in the world Top 10, 20, 50 most air polluted country : According to the 2025 World Air Quality Report based on data from the previous year, Bangladesh is named as the world most polluted country. In 2025, the country had an average Air Quality Index (AQI) of 114 with no months having “good” air quality.
Most Polluted Countries (2025 Rankings)
Based on IQAir reports, the top polluted cities had PM2. 5) are mainly located in South and Central Asia:
Bangladesh
India (Always in top 3-6 ranking range)
Pakistan
Bahrain
Kuwait
United Arab Emirates
Tajikistan
Nepal
Qatar
Saudi Arabia / China
Ranking among countries can vary somewhat between reports (2024/2025) as new monitoring sites are established in previously unmonitored parts of the world and, when this happens, countries like Chad and Congo appear at the top of the list when data exists.
Key Findings
The South Asian Crisis: Bangladesh, Pakistan and India usually score highest because of heavy industrial emissions combined with vehicle traffic, brick kilns and the burning of biomass.
Byrnihat, India: ‘India, as a nation ranks in the top 3-6 but Byrnihat is one of the most polluted cities in the world with Delhi being a hotspot.
WHO Guidelines: More Than 97% of cities in Asia fell below the World Health Organization’s annual PM2. 5 µg/m³) by 2024.
Key Reasons: Poor Air Quality is primarily driven by industrial activities, transportation, burning of agricultural residues and rapid urbanization.
Top 5 Polluted Cities
- Loni, India (No. 1 in 2025)
- Hotan, China
- Byrnihat, India
- Delhi, the most polluted capital in the world
- Faisalabad, Pakistan
In late March 2026, IQAir released its latest World Air Quality Report for the year 2025 and it reaffirmed that South Asia continues to be the world’s most polluted region. The rankings are calculated based on the yearly average concentration of PM2. PM2.5 (fine particulate matter) in $µg/m^3$.
5 $µg/m^3$ is the World Health Organization (WHO) safety guideline. Each of the top 50 countries far exceeds this threshold.
Top 10 Most Air Polluted Countries (2025)
| Rank | Country | Avg. PM2.5 (µg/m3) | Multiple of WHO Limit |
| 1 | Pakistan | 67.3 | 13.5x |
| 2 | Bangladesh | 66.1 | 13.2x |
| 3 | Tajikistan | 57.3 | 11.4x |
| 4 | Chad | 53.6 | 10.7x |
| 5 | DR Congo | 50.2 | 10.0x |
| 6 | India | 48.9 | 9.8x |
| 7 | Kuwait | 45.7 | 9.1x |
| 8 | Uganda | 43.0 | 8.6x |
| 9 | Egypt | 40.6 | 8.1x |
| 10 | Uzbekistan | 38.1 | 7.6x |
Top 11 to 20 Most Polluted Countries
These nations are primarily located in Central Asia, the Middle East, and Africa, where industrial activity and natural desert dust both play major roles.
| Rank | Country | Avg. PM2.5 | Rank | Country | Avg. PM2.5 |
| 11 | Ghana | 35.8 | 16 | Iraq | 31.2 |
| 12 | Burkina Faso | 34.5 | 17 | Nepal | 30.5 |
| 13 | United Arab Emirates | 33.9 | 18 | Bahrain | 29.8 |
| 14 | Kyrgyzstan | 32.7 | 19 | Qatar | 29.2 |
| 15 | Mali | 31.9 | 20 | China | 28.7 |
Regional Breakout: #21 to #50
And while exact decimal-point rankings around positions 21–50 don’t change from month to month, the following countries cement their slot at no. 46 or below thanks to rapid urbanization, seasonal forest fires or high reliance on solid fuels for heating:
Southeast Asia: Vietnam, Indonesia and Thailand (hardest hit by seasonal “haze” and agricultural burning).
The Balkans (Europe): North Macedonia, Serbia and Bosnia & Herzegovina (due to winter burning of wood/coal).
Latin America: Peru and Mexico (urban congestion and industrial clusters)
Central Asia: Kazakhstan and Turkmenistan.
Top 50 Most Air Polluted Countries (2025 Data)
| Rank | Country | Avg. PM2.5 (µg/m3) | Multiple of WHO Limit (5 µg/m3) |
| 1 | Pakistan | 67.3 | 13.5x |
| 2 | Bangladesh | 66.1 | 13.2x |
| 3 | Tajikistan | 57.3 | 11.4x |
| 4 | Chad | 53.6 | 10.7x |
| 5 | DR Congo | 50.2 | 10.0x |
| 6 | India | 48.9 | 9.8x |
| 7 | Kuwait | 45.7 | 9.1x |
| 8 | Uganda | 43.0 | 8.6x |
| 9 | Egypt | 40.6 | 8.1x |
| 10 | Uzbekistan | 38.1 | 7.6x |
| 11 | Ghana | 35.8 | 7.2x |
| 12 | Burkina Faso | 34.5 | 6.9x |
| 13 | United Arab Emirates | 33.9 | 6.8x |
| 14 | Kyrgyzstan | 32.7 | 6.5x |
| 15 | Mali | 31.9 | 6.4x |
| 16 | Iraq | 31.2 | 6.2x |
| 17 | Nepal | 30.5 | 6.1x |
| 18 | Bahrain | 29.8 | 6.0x |
| 19 | Qatar | 29.2 | 5.8x |
| 20 | China | 28.7 | 5.7x |
| 21 | Saudi Arabia | 27.9 | 5.6x |
| 22 | Vietnam | 27.2 | 5.4x |
| 23 | Indonesia | 26.8 | 5.4x |
| 24 | Ethiopia | 26.1 | 5.2x |
| 25 | Nigeria | 25.5 | 5.1x |
| 26 | South Africa | 25.1 | 5.0x |
| 27 | Peru | 24.8 | 5.0x |
| 28 | Thailand | 24.3 | 4.9x |
| 29 | Serbia | 24.1 | 4.8x |
| 30 | Armenia | 23.6 | 4.7x |
| 31 | Turkey | 23.1 | 4.6x |
| 32 | North Macedonia | 22.8 | 4.6x |
| 33 | Bosnia & Herzegovina | 22.4 | 4.5x |
| 34 | Oman | 22.1 | 4.4x |
| 35 | Kazakhstan | 21.8 | 4.4x |
| 36 | Mongolia | 21.4 | 4.3x |
| 37 | Mexico | 21.1 | 4.2x |
| 38 | South Korea | 20.8 | 4.2x |
| 39 | Poland | 20.5 | 4.1x |
| 40 | Bulgaria | 20.2 | 4.0x |
| 41 | Romania | 19.9 | 4.0x |
| 42 | Montenegro | 19.6 | 3.9x |
| 43 | Albania | 19.4 | 3.9x |
| 44 | Greece | 19.1 | 3.8x |
| 45 | Hungary | 18.9 | 3.8x |
| 46 | Chile | 18.6 | 3.7x |
| 47 | Italy | 18.3 | 3.7x |
| 48 | Jordan | 18.1 | 3.6x |
| 49 | Morocco | 17.8 | 3.6x |
| 50 | Cambodia | 17.5 | 3.5x |
Important Global Trends for 2026
India’s slide: it fell from third in previous years into sixth place nationally, havingseen a 3% dip in pollution, albeit its cities (such as Loni and Delhi) make up some of theworld’s most polluted locations.
Wildfire Impact: In 2025 Canada was more polluted than the US for only the second time ever, thanks to record-breaking wildfire seasons that also raised levels in much of the northern US and parts of Europe.
The “Cleanest” Few: Only 13 countries/territories met the WHO guideline in 2025, such as Australia, Iceland, Estonia and French Polynesia.
