Most Populated Cities in the World: The New UN Ranking, and Why Tokyo Fell

Jakarta is now the most populated city in the world, with about 41.9 million people, according to the United Nations' World Urbanization Prospects 2025, published in November 2025. Dhaka is second at roughly 36.6 million, and Tokyo, which topped almost every list for half a century, has dropped to third at 33.4 million. New Delhi is fourth at 30.2 million. Kolkata (ninth) and Mumbai (twelfth) give India three places in the top twelve.

If you have seen a list with Tokyo first at about 37 million and Delhi second, it isn't wrong. It measures a different thing. The UN changed where it draws the edge of a city, and the whole table moved. Here is the ranking, why it changed, and what a city of 30 million does to the price of a home.

Key takeaways

• The UN's 2025 figures put Jakarta first at about 41.9 million, then Dhaka at 36.6 million and Tokyo at 33.4 million.
• For the first time the UN applied one satellite-based density rule to every country, called the Degree of Urbanisation, instead of each government's own definition of a city.
• Delhi is fourth at 30.2 million, Kolkata ninth at about 22.6 million and Mumbai twelfth at 20.2 million.
• There were 33 megacities of 10 million or more in 2025, against 8 in 1975. Nineteen of them are in Asia.
• The UN expects Dhaka to be the largest city by 2050, at about 52.1 million, with Tokyo sliding to seventh.
• Lists that still show Tokyo on top come from the UN's older (2018) projections, which still circulate widely.

The top 20 most populated cities in the world

Three notes. The UN's press release called Dhaka "almost 40 million", while its published city table shows 36.6 million; we've used the table. Kolkata appears as 22.6 million in some reproductions and 22.5 million in others, which is rounding. And the order from 18th to 20th differs between the sources we could check, so we've printed it as a band rather than guess.

Why Tokyo is no longer number one

Nothing dramatic happened in Tokyo. The ruler changed. There are at least four ways to measure a city, and each gives a different answer.

• City proper. The administrative boundary: a municipal corporation or a set of wards. Some governments draw it tight, others wide, so it compares poorly.
• Urban agglomeration. The continuous built-up area around a core. This is what the earlier UN series used, but each country supplied its own definition, so Japan's version of an agglomeration was not the same as Indonesia's.
• Metropolitan area. The commuting region, which often includes satellite towns and the farmland between them. India's National Capital Region is a planning version of this.
• Degree of Urbanisation. The new UN method. It lays a grid of one-square-kilometre cells over satellite and census data and calls a city any continuous cluster of cells with at least about 1,500 people per square kilometre and at least 50,000 people in total. The same rule applies in every country.

Under that rule, Tokyo loses population on paper because its old figure took in the whole Tokyo-Yokohama region, including outer suburbs that thin out below the density line. Japan's population is also shrinking. Jakarta gains because its dense built-up area runs without a break through Bogor, Depok, Tangerang and Bekasi, and the new method counts all of it where the older figure followed a far narrower boundary. Dhaka and Kolkata gain for the same reason: very dense settlement that spills past the official city limits.

Why the old list is still everywhere

Many older lists that still circulate are built on the UN's 2018 projections. That is why they still read Tokyo first. Demographia's World Urban Areas report measures built-up area from its own mapping and produces a different order again. None is a mistake; they answer different questions. Here is how far apart the two approaches sit for five cities.

The rule of thumb: a city's population without its boundary is not comparable with anything.

India's cities in the ranking

India has three cities in the UN's top twelve. Only China matches that in the top twenty, with Shanghai, Guangzhou and Beijing.

Delhi, fourth at 30.2 million

Under the older UN series, Delhi was projected to overtake Tokyo and become the world's largest city around 2028. The new method puts it fourth instead, at 30.2 million, largely because the density rule draws its edge tighter than a wide agglomeration does. The growth itself is real. Most of it now happens outside the old city, in Gurugram, Noida, Ghaziabad and Faridabad, which are counted as part of Delhi's city wherever the built-up area is continuous.

Kolkata, ninth at about 22.6 million

Kolkata surprises many readers. The new method rewards what it has always been: a very dense belt of settlement along both banks of the Hooghly that runs well beyond the municipal corporation. It is also the most affordable of the three cities, with the top end of its market far below Mumbai's; our list of the most expensive flats in Kolkata shows the ceiling.

Mumbai, twelfth at 20.2 million

Mumbai's geography is its limit. The island city cannot spread, so growth has gone north and east to Thane, Navi Mumbai and beyond. That is why the Mumbai region, not the city, is where most new homes are sold. Our Mumbai real estate market guide covers how prices differ across that spread.

The UN's projections add one more Indian name worth knowing. Hajipur, in Bihar, is among the places the UN expects to pass 10 million people by 2050. That says as much about the method as about Bihar: dense settlement that official maps treat as villages and small towns now counts as one city where it runs together.

Where the world's biggest cities are heading

The same report says cities now hold 45% of the world's 8.2 billion people. The number of megacities has quadrupled in 50 years, from 8 in 1975 to 33 in 2025, and the UN expects 37 by 2050, with Addis Ababa, Dar es Salaam, Hajipur and Kuala Lumpur among the new entries.

Dhaka is the city to watch. The UN projects it at about 52.1 million by 2050, which would make it the largest city on earth, with Tokyo down to seventh. Cairo is the only city outside Asia in today's top ten, and two of the four new megacities the UN expects by 2050 are in Africa.

What 30 million people do to a housing market

A city of 30 million has a simple problem: the land in the middle is full. Delhi's density was above 11,000 people per square kilometre at the 2011 census, and the core has had little room for new housing since. When demand keeps growing and the centre can't absorb it, homes get built wherever land can be assembled in large parcels and reached in reasonable time. In the Delhi region that means Gurugram, Noida, Greater Noida, Ghaziabad and Faridabad.

The prices show it. ANAROCK puts Gurugram's average at about Rs 13,350 per sq ft in the April-June quarter of 2026, up from Rs 6,150 in 2019. One widely quoted series has Dwarka Expressway at a little over Rs 9,600 per sq ft in early 2026, against Rs 5,359 in 2019. First-half 2026 figures reported in the business press had Delhi and Faridabad up about 18% on the year, Ghaziabad 15% and Noida 8%, though the coverage we could find does not name the research house behind them. Our Delhi NCR property prices breakdown goes sub-market by sub-market.

Why homes move to the edge along roads and rail

• Distance becomes time. An expressway or metro line turns 30 kilometres into 40 minutes, and buyers price commute time, not kilometres.
• Land is cheaper at the edge. A developer can put together 20 or 50 acres there, which is close to impossible in a built-up core.
• Jobs follow the same lines. Offices, warehouses and campuses cluster at interchanges, which pulls housing demand behind them.

The risk is the mirror image. Edge markets often run ahead of the roads, water and schools they need, and when sales slow the edge feels it first. PropEquity counted Delhi-NCR sales down 12% year on year in the July-September quarter. If you are buying on a corridor, buy what is already connected or close to it, and check a project's delivery record before its brochure; our current projects list is a starting point.

Dubai, the contrast

Dubai grows the opposite way. Its population went past about 4 million in 2025 by the official Dubai Statistics Center count, tiny next to Delhi, but it grows mainly through people moving in for work. New supply comes as planned master communities along Sheikh Zayed Road, the metro and the routes to the second airport, so the city expands to the edge on purpose rather than by spillover. You can see how that plays out by area on our Dubai properties page.

Frequently asked questions

Which is the most populated city in the world?

Jakarta in Indonesia, with about 41.9 million people, on the UN's World Urbanization Prospects 2025. Dhaka is second at about 36.6 million and Tokyo third at 33.4 million. The UN reached that order by measuring every city with the same satellite-based density rule.

Why do some lists still show Tokyo as the largest city?

They use the UN's earlier method, which relied on each country's own definition of a city and counted the full Tokyo-Yokohama region at about 37 million. The 2025 method counts only continuous dense settlement, which trims Tokyo and adds to cities like Jakarta and Dhaka whose built-up areas spill past their official limits.

What is the population of Delhi?

About 30.2 million on the UN's 2025 method, which ranks Delhi fourth in the world. Older-method trackers put it near 34.7 million because they draw a wider boundary. Neither figure is the population of the National Capital Territory alone, which is smaller.

Which Indian cities are among the largest in the world?

Delhi is fourth at 30.2 million, Kolkata ninth at about 22.6 million and Mumbai twelfth at 20.2 million. The UN also expects Hajipur in Bihar to pass 10 million people by 2050.

Which city will be the largest in the world by 2050?

Dhaka, according to the UN, at about 52.1 million people. On the same projection Tokyo falls to seventh, and the number of megacities worldwide rises from 33 to 37.

If a city's growth is part of why you're thinking about buying, whether in the Delhi region, Mumbai or Dubai, Realty Hunting can walk you through which corridors are already connected and which are still a promise.

Sources

The figures and rules in this post were researched against these sources. Government and regulator sources are listed first. Rates, fees and rules change; check the current figure with the authority before you pay or sign.

1. dsc.gov.ae (official)
2. un.org
3. un.org
4. population.un.org
5. visualcapitalist.com
6. nbcnews.com
7. archdaily.com
8. worldpopulationreview.com
9. gulfnews.com
10. businesstoday.in
11. businesstoday.in
12. businesstoday.in