Megacities Continue Growing
The world is becoming increasingly urban, with cities now home to 45 percent of the global population of 8.2 billion, according to the World Urbanization Prospects 2025: Summary of Results, released by the United Nations Department of Economic and Social Affairs (UN DESA). The number of people living in cities has more than doubled since 1950, when only 20 percent of the world’s 2.5 billion people lived in cities. Looking ahead through 2050, two-thirds of global population growth is projected to occur in cities, and most of the remaining one-third in towns.
What Is A Megacity?
The number of megacities, urban areas with 10 million or more inhabitants, has quadrupled from eight in 1975 to 33 in 2025. More than half of these megacities (19) are in Asia.
Jakarta (Indonesia) is now the world’s most populous city, with nearly 42 million residents, followed by Dhaka (Bangladesh) with almost 40 million, and Tokyo (Japan) with 33 million. Cairo (Egypt) is the only non-Asian city among the top ten. By 2050, the number of megacities is expected to rise to 37, with cities such as Addis Ababa (Ethiopia), Dar es Salaam (United Republic of Tanzania), Hajipur (India), and Kuala Lumpur (Malaysia) projected to surpass the 10 million mark.
Despite the prominence of megacities, the report finds that small and medium-sized cities are home to more people than megacities and are growing at a faster pace, particularly in Africa and Asia. Of the 12,000 cities analyzed, 96 percent have fewer than one million inhabitants, and 81 percent have fewer than 250,000.
The new data show that the total number of cities worldwide more than doubled between 1975 and 2025, and projections indicate that by 2050, the number of cities worldwide could exceed 15,000, with most having populations below 250,000.
The report also highlights the divergent growth patterns of cities. While many cities continue to expand, others are experiencing population decline. Notably, some city populations are shrinking even as their countries’ populations grow, while others are growing despite the decline of the national population. Most shrinking cities had fewer than 250,000 inhabitants in 2025, with over one-third located in China and 17 percent in India. However, some very large cities, including Mexico City and Chengdu, China, have also seen population decreases.
The Future Of Towns and Rural Areas
Towns, defined as population clusters of at least 5,000 inhabitants and a density of at least 300 people per square kilometer, are the most common settlement type in 71 countries as diverse as Germany, India, Uganda, and the United States. They connect rural areas and cities, offering essential services and supporting local economies.
Rural areas remain the most common settlement type in 62 countries today, down from 116 in 1975. By 2050, this number is projected to decline further to 44 countries. Rural settlements still dominate in some countries in Europe including Austria, Bulgaria, Finland, and Romania, as well as in numerous countries in sub-Saharan Africa, such as the Central African Republic, Chad, Eswatini, Mozambique and Zambia. Sub-Saharan Africa is the only region where rural populations have continued to grow significantly, and the region is expected to account for nearly all future rural population growth.
“The United Nations underscores the pivotal role of urbanization in driving sustainable development and climate resilience across all settlement types,” said Li Junhua, United Nations Under-Secretary-General for Economic and Social Affairs. “Urbanization is a defining force of our time. When managed inclusively and strategically, it can unlock transformative pathways for climate action, economic growth, and social equity. To achieve balanced territorial development, countries must adopt integrated national policies that align housing, land use, mobility, and public services across urban and rural areas.”
The World Urbanization Prospects 2025: Summary of Results provides a critical evidence base for policymakers, planners, and researchers working to shape sustainable, inclusive, and resilient urban futures. For more information, visit population.un.org.
Greener Cities is a division of Crossbow Communications. Greener Cities is a resource for sustainable and resilient cities and communities around the world.
