Jakarta is now the most populous city and in another 25 years, Dhaka will have that distinction, says a UN report. Cities in Asia’s emerging economies are now the global urban hotspots with their unique infrastructural challenges, requiring urban planners to find sustainable solutions, writes Banasree Purkayastha
Nine out of ten top cities in Asia, Jakarta at No. 1
The urban population boom in Asia’s emerging economies as citizens migrate to big cities is outpacing that of established urban hotspots like Tokyo. Jakarta, the capital of Indonesia, was the world’s most populous city in 2025, with close to 42 million inhabitants, pushing Tokyo, the top ranker in 2000, down to third place, a recent United Nations report shows. Dhaka followed Jakarta with nearly 37 million inhabitants. Tokyo, in contrast, had 33.4 million inhabitants as a greying society made its impact visible.
As per the UN World Urbanisation Prospects report, nine of the ten most populous cities in 2025 are in Asia—Delhi at fourth position with a population of 30.2 million, followed by Shanghai (No.5) with 29.6 million, Guangzhou (No.6) with 27.6 million and Manila (No.8) with 24.7 million. Kolkata and Seoul shared the ninth spot with 22.5 million inhabitants each.
Cairo, at seventh spot, is the only city among the top ten in 2025 that is not located in Asia.
By 2050, Dhaka to take over as most populous city
BY 2050, the changes will be more stark. Dhaka and Shanghai are expected to grow the fastest among 2025’s ten most populous cities, with annual projected growth rate close to 5% between 2025 and 2050. By mid-century, Dhaka is set to overtake Jakarta as the world’s largest city, while Shanghai is expected to move up to third place. Karachi is likely to enter the top ten list by 2030 and rank fifth by 2050.
Meanwhile, Tokyo is projected to fall from third place in 2025 to seventh in 2050, as its population shrinks to around 31 million. Cairo is expected to move up to sixth place while Guangzhou and Manila are likely to slip to the eighth and ninth position, respectively. Coming to Indian cities, Delhi will retain its fourth position with 33.9 million people while Kolkata will take the tenth spot with its 23.8 million inhabitants.
Rise of the megapolis
Cities are now home to about 45% of the world’s 8.2 billion people—more than double the urban share in 1950. Contrast this with 1950 when only 20% of the world’s 2.5 billion people lived in cities. India, China, Nigeria, Pakistan and the USA collectively contribute over 500 million people to the global city population.
In 2025, there were more than 12,000 unique cities globally. These include 33 megacities with more than 10 million inhabitants each, 49 large cities with 5-10 million inhabitants, 429 medium-sized cities with 1-5 million inhabitants, 1,822 small cities with 250,000 to 1 million inhabitants, and 9,807 very small cities with less than 250,000 inhabitants. Most megacities are located in the global South. Among the 33 megacities with 10 million inhabitants or more in 2025, 19 are in Asia. India alone has five megacities, and China has four.
Small cities are losing their charm
More than 3,000 cities saw population decline between 2015 and 2025. More than one third of the world’s cities with shrinking population are in China, while 17% are in India. Small and medium-sized cities in India are losing residents due to demographic decline and migration to big cities. A number of countries including China, Germany, Italy, Japan, Poland, South Korea and Taiwan, are likely to see urban population fall by over 1 million by 2050. China and Japan are likely to lose 26 million and 12 million city residents, respectively, as population declines.
Measuring urbanisation
The 2025 UN report integrates new geospatial methods of estimation through the harmonised ‘Degree of Urbanisation’ methodology, alongside country-specific definitions. This method classifies the entire area of a country along the urban-rural continuum based on population size and density thresholds applied to 1 square km²grid cells. It identifies three main types of areas: cities (densely populated areas), towns and semi-dense areas (intermediate density areas, often representing the transition between rural and urban) and rural areas (thinly populated areas). This allows researchers to measure cities, towns and rural areas consistently across countries and over time, while still retaining results based on national definitions for domestic policy use and statistical continuity.
Importance of these findings
The population growth in cities and towns has implications for economic and social development, as well as environmental sustainability. Cities with rapid population growth, many of which are in poorer countries, require inclusive urban planning to ensure affordable housing and transportation, as well as clean water, sanitation and healthcare. As the report says, understanding urbanisation is vital not only for measuring demographic trends accurately but also for guiding sustainable development strategies that ensure urban areas become thriving engines of equitable growth and resilience.