World's 10 Largest Cities by Population (2018 UN Estimates)

Based on United Nations World Urbanization Prospects 2018 (urban agglomeration populations):

1. Tokyo, Japan — 37.0 million
2. Delhi, India — 28.5 million
3. Shanghai, China — 26.3 million
4. Beijing, China — 21.5 million
5. Mumbai, India — 18.4 million
6. Cairo, Egypt — 17.9 million
7. Karachi, Pakistan — 16.0 million
8. Istanbul, Turkey — 15.5 million
9. Mexico City, Mexico — 14.9 million
10. Dhaka, Bangladesh — 14.4 million

Important Notes

• Definition matters: "City proper" vs. "urban agglomeration" vs. "metro area" yield different rankings
• Chongqing, China (32M admin area) often cited but includes vast rural territory
• Post-2018 growth: African cities (Kinshasa, Lagos, Luanda) rising fast
• 2023 estimates: Tokyo ~37M, Delhi ~33M, Shanghai ~29M, São Paulo ~22M, Mexico City ~22M

Regional Distribution

• Asia: 7 of top 10
• Africa: 1 (Cairo)
• Latin America: 1 (Mexico City)
• Europe/North America: 0 in top 10

Megacity Threshold

UN defines "megacity" as >10 million. In 2018: 33 megacities. Projected 43 by 2030.