For decades, Tokyo has been synonymous with urban sprawl and dense city life, topping the charts as the world’s largest metropolis. But that era has come to an end. According to the latest United Nations report on urbanization prospects, released on January 1, 2026, Jakarta has now claimed the title of the world’s largest city, boasting a staggering 41.9 million inhabitants. Hot on its heels is Dhaka, while Tokyo, once the reigning giant, has slipped down to third place. This seismic shift in urban rankings reflects not only the relentless growth of developing megacities but also the demographic challenges facing Japan’s capital.
The United Nations’ Department of Economic and Social Affairs (DESA) introduced a new methodology for city population counts, focusing on urban agglomerations—essentially, any contiguous area with at least 1,500 inhabitants per square kilometer and a minimum population of 50,000. Using this yardstick, Tokyo’s urban count includes neighboring prefectures like Saitama, Chiba, and Kanagawa, rather than just the administrative city proper, which has about 14 million residents. This approach provides a more apples-to-apples comparison between global cities, especially those sprawling across administrative boundaries.
What’s driving Jakarta’s meteoric rise? The answer lies in the explosive urban growth typical of many developing nations. Jakarta, Indonesia’s bustling capital, has seen its population soar to approximately 42 million, while Dhaka, the capital of Bangladesh, has surged to around 37 million. Tokyo, meanwhile, sits at roughly 33 million. These numbers, reported by Kyodo News and corroborated by the UN, signal a broader trend: the urban population boom in Asia’s emerging economies is outpacing that of established giants like Tokyo.
This isn’t just a numbers game, either. The UN report highlights that cities now house about 45 percent of the world’s 8.2 billion people—more than double the urban share in 1950. And the trend shows no sign of slowing. Between 2025 and 2050, an estimated two-thirds of the world’s population growth is expected to occur in cities, with most of the remainder in smaller towns. As urbanization accelerates, the ability to manage city growth sustainably is becoming crucial—not just for the well-being of urban dwellers, but for progress on global climate goals as well. The data, as the UN emphasizes, is intended to help policymakers and researchers shape the cities of tomorrow.
But if some cities are swelling, others are shrinking. The UN report notes that Japan and China are among a growing list of countries expected to see significant urban population declines by 2050. The culprit? Persistently low birth rates and overall population decline. In Japan, for example, the total population shrank by about 4 million between 2015 and 2025, even as Tokyo managed to add over 300,000 residents during that period. However, this growth is expected to reverse course. The Tokyo urban area is projected to shrink from 33.4 million in 2025 to 30.7 million by 2050, dropping the city to seventh place globally.
Tokyo and Seoul are the only two cities among the world’s ten largest in 2025 that are forecast to experience a population decline by mid-century. This demographic headwind is poised to reshape the urban landscape of East Asia, shifting the focus to the surging megacities of South and Southeast Asia. By 2050, Dhaka is projected to be the world’s largest city with 52.1 million residents, followed by Jakarta, Shanghai, New Delhi, Karachi, and Cairo. Tokyo, once the epitome of urban might, will find itself further down the list.
What does this mean for the cities themselves—and for those who visit them? According to Explore, a travel publication, the experience of traversing these urban giants varies dramatically. Tokyo, Shanghai, and Seoul stand out as some of the easiest and most pleasant cities to visit, offering efficient public transit, orderly infrastructure, and a sense of urban calm amid the crowds. In contrast, Jakarta and Dhaka present challenges for the intrepid traveler: traffic congestion, limited public transit, and haphazard urban development can make these cities difficult to navigate. Yet, for those willing to dive into the chaos, both cities offer unique rewards.
Jakarta, for instance, is known for its notorious traffic jams and a single subway line, making it less walkable than its East Asian counterparts. But the city’s Old Town, with its colonial-era buildings and the Jakarta History Museum, offers a glimpse into Indonesia’s past. Café Batavia, housed in an elegant early-19th-century building, provides a welcome respite from the urban hustle. Beyond the Old Town, Glodok—Jakarta’s Chinatown—is a maze of alleyways and traditional shops, while the city’s many malls cater to every taste and budget.
Dhaka, too, is a city of contrasts. Traffic is, by all accounts, challenging, and driving is not for the faint of heart. Instead, visitors are encouraged to hop into an autorickshaw and plunge into the action at Sadarghat, the city’s teeming river port. Here, ferries and wooden boats jostle for space, and daily life unfolds along the water’s edge. Shankharia Bazar, with its colorful buildings and artisan workshops, offers another side of Dhaka—a place to pick up a unique souvenir and witness the city’s vibrant craft traditions.
Despite their challenges, Jakarta and Dhaka are drawing attention not just for their size, but for the experiences they offer. As Explore notes, “While the megacities of Jakarta and Dhaka may not be as easy to explore as Tokyo, they offer different, rewarding experiences and the bragging rights of having visited the world’s most populous cities.” For adventurous travelers, the chance to immerse themselves in the world’s new urban giants is a compelling draw.
The shifting rankings of the world’s largest cities also carry important implications for global policy. As urban populations swell in places like Jakarta and Dhaka, the need for sustainable infrastructure, effective governance, and climate resilience becomes more acute. Conversely, cities like Tokyo and Seoul must grapple with the challenges of population decline—aging infrastructure, shrinking workforces, and the risk of economic stagnation.
In the end, the story of the world’s largest cities is one of constant change. The rise of Jakarta and Dhaka signals a new era in global urbanization, driven by demographic shifts, economic growth, and the relentless march of people toward city life. For Tokyo, the challenge is to adapt to a future where size is no longer its defining feature, but innovation and quality of life may well be.
As the world’s urban landscape continues to evolve, so too will the cities at its heart—each with its own challenges, opportunities, and stories to tell.
