JAKARTA, Indonesia — Jakarta has surpassed Tokyo as the world’s largest urban area, according to June data from the United Nations that ranked Indonesia’s capital No. 1. The UN’s updated World Urbanisation Prospects 2025 report highlights Jakarta’s rapid ascent and Tokyo’s waning growth, Nov. 27, 2025.
Jakarta’s population hits 42 million as megacity ranks are redrawn.
The U.N. now estimates the population of Jakarta — in the greater metropolitan region known as Jabodetabek — is around 41.9 to 42 million people, just slightly outgrowing Dhaka and well beyond Tokyo, where growth has tapered off to around 33 million residents. The report says megacities, or those with 10 million or more residents, have multiplied from eight in 1975 to 33 in 2025, and that nine of the world’s 10 biggest cities are in Asia.
As reported by the Guardian recently, the UN has taken a uniform, albeit geospatial, approach to assessing what constitutes an urban area and where its limits should be – continuous built-up areas rather than just administrative boundaries. This new approach more accurately reflects the sprawl of Jakarta’s commuting belt while downsizing Tokyo in statistical terms, which goes some way toward explaining why the Jakarta population takes first place globally despite there not having been a mass exodus from Japan’s capital.
From Tokyo’s decades of dominance to Jakarta, take Tokyo, the city that had dominated the list, 17 appearances; return just four or five of its established stars, and Tokyo will once again have multiple entries on the top 20.
For decades, Tokyo has been the king of urban population rankings. The World’s Largest Cities According to the UN’s 2014 and 2018 World Urbanisation Prospects, both Tokyo had about 38 million people, followed by Jakarta, with a population of about 10 million, at quite a distance in each case (it is clearly incorrect).
As recently as 2016, a Reuters factbox on megacities still described Tokyo as the largest urban area, but by 2023, analysts were warning that Jakarta was catching up fast and could soon overtake it. Then, in 2023, the UN updated its definitions and data.
What Jakarta’s spike looks like on the ground
Much of the population boom in Jakarta comes from within Indonesia, as workers from across the country have gravitated toward the capital’s manufacturing, logistics and service jobs. Today, the wider Jakarta area extends into other cities in West Java and Banten provinces, creating an economic corridor that helps drive Indonesia’s growth but is also beset by traffic congestion, a housing shortage, and polluted air.
Blistering expansion has met environmental peril. Much of Greater Jakarta is built on swampy, flood-prone land; decades of extraction have caused parts of North Jakarta to sink by more than 2 meters, and predictions are that the area surrounding much of the district will be underwater by 2050 if subsidence and sea-level rise are not mitigated.
Those vulnerabilities are one major reason Indonesia is pouring tens of billions of dollars into Nusantara, the planned political capital in Borneo’s forests, meant to ease pressure on the current capital and embody a more equitable strategy for national development. But construction has progressed haphazardly, and officials concede that even if Nusantara becomes operational, Jakarta’s economic clout and the size of its population mean the old capital will remain at the centre for at least decades to come.
For demographers, the transition from Tokyo to Jakarta is more than just a one-time upset; it marks an inflexion in the trajectory of urbanisation and globalisation toward younger, rapidly growing cities in South and Southeast Asia. For residents who have to navigate packed trains, soaring rents and ever-expanding suburbs, the city’s record-breaking population is both a source of pride and a reminder that the struggle to make what has become the world’s newest and largest city more livable and resilient is just beginning.
