Largest Cities in the World by Population (2026 Rankings Updated)

Tokyo is still the world’s largest city — but not for much longer. With Delhi adding hundreds of thousands of residents every year and several African cities doubling in size within a generation, the global urban map is being redrawn in real time. By 2050, the United Nations projects that two-thirds of all humanity will live in cities. Understanding which cities are growing, why, and what that growth looks like on the ground is one of the most urgent questions in contemporary urban planning and architecture.

This ranked list covers the 20 largest cities in the world by population in 2026, using urban agglomeration figures — the most accurate measure of how many people actually live within a city’s full metropolitan footprint. For each city, we’ve gone beyond the numbers to look at the urban challenges shaping each place, and what their architecture and skylines reveal about how they’re responding.

What Is a Megacity?

The United Nations defines a megacity as an urban agglomeration with a population of 10 million or more. As of 2026, there are approximately 35 megacities worldwide — up from just two (Tokyo and New York) in 1950. Asia alone accounts for more than 20 of them. The term “urban agglomeration” matters here: it includes not just the official city limits, but the full continuous built-up area and its surrounding suburbs, which is why these numbers often differ significantly from what you’ll find on a city’s Wikipedia page.

The 20 Largest Cities in the World by Population (2026)

All population figures below are estimated urban agglomeration data for 2026, based on UN World Urbanization Prospects and World Population Review projections.

#	City	Country	Est. Population (2026)	Continent
1	Tokyo	Japan	37,115,000	Asia
2	Delhi	India	34,700,000	Asia
3	Shanghai	China	29,210,000	Asia
4	Dhaka	Bangladesh	23,900,000	Asia
5	São Paulo	Brazil	23,090,000	South America
6	Mexico City	Mexico	22,505,000	North America
7	Cairo	Egypt	22,180,000	Africa
8	Beijing	China	21,766,000	Asia
9	Mumbai	India	21,673,000	Asia
10	Osaka	Japan	19,059,000	Asia
11	Chongqing	China	17,943,000	Asia
12	Karachi	Pakistan	17,440,000	Asia
13	Kinshasa	DR Congo	17,071,000	Africa
14	Lagos	Nigeria	16,637,000	Africa
15	Istanbul	Turkey	16,047,000	Europe / Asia
16	Buenos Aires	Argentina	15,618,000	South America
17	Kolkata	India	15,332,000	Asia
18	Manila	Philippines	14,800,000	Asia
19	Guangzhou	China	14,512,000	Asia
20	Moscow	Russia	12,641,000	Europe

Source: UN World Urbanization Prospects; World Population Review — 2026 estimates. All figures reflect urban agglomeration, not administrative city limits.

The 10 Largest Cities in the World: Full Profiles

1. Tokyo, Japan — Est. Population 2026: 37,115,000

Tokyo houses roughly 30% of Japan’s entire population within its greater metropolitan area — a statistic that would seem improbable if you hadn’t seen the city’s extraordinary density with your own eyes. What began as the small fishing village of Edo grew over centuries to become the first megacity in Asia and, for decades, the largest urban agglomeration on Earth.

The only event to significantly disrupt Tokyo’s growth was World War II. Even then, the city recovered its pre-war population in less than a decade — a testament to both the resilience of its residents and the efficiency of Japanese urban policy. Today, Tokyo operates on remarkably low natural resources relative to its size, particularly land. The response has been architectural: Tokyo goes up. Its skyline is a compressed vertical city, and its rail network — carrying more passengers than any other in the world — is the invisible infrastructure that holds it all together.

Architectural signature: Tokyo is defined by its layered urbanism — expressways elevated above street level, rail lines threading between mid-rise buildings, and a street grid that defies Western geometric logic. Neighborhoods like Shinjuku and Shibuya read as cities within a city, each with its own skyline and character.

Tokyo’s population is gradually declining, driven by Japan’s aging demographics and one of the world’s lowest birth rates. It will likely slip from the top spot by around 2028.

2. Delhi, India — Est. Population 2026: 34,700,000

Delhi — officially the National Capital Territory (NCT) of India — is on a collision course with the top of this list. With a combination of high birth rates and massive internal migration from rural India, Delhi is adding the equivalent of a mid-sized European city to its population every two to three years. The UN projects it will overtake Tokyo and become the world’s most populous city by approximately 2028 to 2030.

Delhi has been the center of Indian civilization for millennia, housing empires from the Mughals to the British Raj, each of which left a distinct architectural mark. Lutyens’ Delhi — the imperial city-within-the-city designed by Edwin Lutyens for the British colonial administration — remains one of the most formally planned urban quarters in Asia, a sharp contrast to the organic density of Old Delhi’s lanes and bazaars.

Architectural signature: Delhi is perhaps the world’s most layered city architecturally. Ancient mosques, Mughal tombs, colonial bungalows, and gleaming glass corporate towers coexist within blocks of each other. The Delhi Metro, now one of the largest rapid transit systems in the world, is the city’s most important piece of new urban infrastructure, threading together a dispersed metropolitan area that would otherwise be gridlocked.

The challenges ahead for Delhi’s planners are enormous: delivering adequate housing, clean air, water, and sanitation to a city that may soon hold 40 million people.

Also read: The most famous Indian architecture

3. Shanghai, China — Est. Population 2026: 29,210,000

There’s a reason Shanghai is called the Pearl of the Orient and the Paris of the East — it has always operated as something other than a typical Chinese city. It’s a global financial center, a fashion capital, and an architectural showcase all at once, and its Pudong skyline — built almost entirely since the 1990s — is arguably the most dramatic statement of rapid urban development anywhere in the world.

Shanghai’s population has historically been managed by policy. China’s one-child policy, in effect for decades, significantly shaped the city’s demographics, limiting the kind of unchecked urban growth seen in Delhi or Dhaka. While this kept resources more manageable, it created downstream challenges: an aging population, a low fertility rate, and a gender imbalance that continues to have social and economic consequences. China has since introduced incentives — including financial bonuses and extended parental leave — to encourage younger families to settle in the city.

Architectural signature: The juxtaposition of the Bund — Shanghai’s riverfront promenade of European Art Deco and neoclassical bank buildings from the 1920s and 30s — directly facing the hypermodern glass towers of Pudong is one of the most striking urban vistas in the world. It is, in one view, a hundred years of global capitalism compressed into a single panorama.

4. Dhaka, Bangladesh — Est. Population 2026: 23,900,000

Dhaka has climbed from #6 in 2021 to #4 in the global rankings — one of the most striking rises of any megacity this decade. Called the City of Mosques, Dhaka is Bangladesh’s industrial and financial heartbeat, driven primarily by the country’s enormous textile and garment export industry. It is one of the most densely populated major cities on Earth, with some central neighborhoods exceeding 40,000 people per square kilometer.

The city’s growth is largely the product of two forces: a vibrant manufacturing economy that pulls workers from rural areas, and high birth rates that sustain the natural population increase. The result is a city that has grown faster than its infrastructure can accommodate — drinking water shortages, severe air pollution, and daily traffic gridlock are persistent realities for millions of residents.

Architectural signature: Dhaka’s built environment is largely self-organized — a vast, informal city that has grown through improvisation rather than master planning. The contrast between the colonial-era Old Dhaka, with its narrow streets and traditional courtyard houses, and the newer high-rise commercial corridors of Gulshan and Banani tells the story of a city trying to build a formal urban identity while managing explosive informal growth simultaneously.

Dhaka needs a comprehensive urban planning intervention urgently — particularly around flood resilience, given its location in the Ganges-Brahmaputra delta, one of the world’s most climate-vulnerable regions.

5. São Paulo, Brazil — Est. Population 2026: 23,090,000

São Paulo is South America’s largest city and one of its most ethnically complex — waves of Italian, Japanese, Lebanese, German, and Spanish immigrants over the past century have made it the most culturally diverse city in Brazil. That cultural richness powers a world-class arts, gastronomy, and design scene. São Paulo’s São Paulo Art Museum (MASP), suspended above Paulista Avenue on its bold concrete pillars, is one of the most architecturally iconic museum buildings in the Western Hemisphere.

But the same forces that made São Paulo great — its economic magnetism pulling migrants from across Brazil and the world — have also made it deeply unequal. Inadequate housing, crumbling infrastructure in peripheral neighborhoods, severe traffic, and air and water pollution are consequences of growth that outpaced planning by decades. Brazil’s responses have ranged from slum upgrading programs (providing residents with building materials and land tenure rather than demolishing informal settlements) to major expansions of the metro system.

Architectural signature: São Paulo is defined by its density and its verticality. With land prices in the center among the highest in Latin America, the city goes up — an almost unbroken canopy of high-rises extending in every direction. Its street art scene, some of the richest in the world, covers every surface below the roofline.

Also read: The most iconic buildings in modern architecture

6. Mexico City, Mexico — Est. Population 2026: 22,505,000

Mexico City presents a unique urban planning paradox: a city that isn’t growing especially fast (its population growth rate is relatively low compared to other megacities), yet remains chronically unable to keep up with the infrastructure demands of the population it already has. The result is a city of stark contrasts — gleaming corporate corridors in Polanco and Santa Fe alongside some of Latin America’s largest informal settlements.

There’s a geographical dimension to Mexico City’s challenges that has no easy fix: the city sits in a high-altitude basin, trapped between two large mountain ranges. This geography funnels and traps air pollution, creating a persistent smog problem and amplifying the urban heat island effect. The city has invested significantly in zero-emission transit — its Metrobús rapid transit network, Ecobici bike-sharing system, and electric trolleybus lines are among the most extensive in Latin America — as partial answers to this structural problem.

Architectural signature: Mexico City’s urban core is one of the richest layers of history in the Americas. The Zócalo, one of the largest public squares in the world, sits directly above the ruins of Tenochtitlan, the Aztec capital. Aztec foundations, Spanish Baroque churches, 19th-century Haussmann-influenced boulevards, and Luis Barragán’s modernist houses all coexist within a few kilometers of each other. Mexico City is essentially a vertical excavation of architectural history.

7. Cairo, Egypt — Est. Population 2026: 22,180,000

Cairo — often called the Cradle of Civilization — is the largest city in Africa and the Arab world, a place where 5,000 years of human settlement are layered in the city’s fabric, sometimes literally visible in its street level archaeology. It connects ancient Egypt to modern Egypt in a way no other city can, with the Pyramids of Giza visible from the city’s western districts on a clear day.

Cairo’s population growth is driven by a significant gap between birth and death rates, and by sustained rural-to-urban migration from the Nile Delta and Upper Egypt. This has produced serious air quality problems — Cairo ranks among the world’s most air-polluted capitals — and severe pressures on housing, utilities, and transport. Egypt’s response has been dramatic: the construction of a brand-new administrative capital, New Administrative Capital, about 45 kilometers east of Cairo, intended to eventually house millions of civil servants and relieve pressure on the historic city. It is one of the most ambitious planned city projects anywhere in the world.

Architectural signature: Cairo is a city of minarets and medieval street patterns in Old Cairo, Ottoman-era merchant houses in Khan el-Khalili, and Khedivial-era Haussmann boulevards in Downtown Cairo — all now overlaid with the informal concrete construction that characterizes its outer districts. The contrast between this historic core and the gleaming glass towers rising in the New Administrative Capital is a powerful statement about where Egypt’s ambitions are pointed.

8. Beijing, China — Est. Population 2026: 21,766,000

Beijing is China’s capital and its second-largest city, and it is managed more deliberately than almost any other megacity on Earth. The city’s population grew by a remarkable 44% in a single decade between 2000 and 2010. But China’s five-year planning approach put a hard cap on that growth: a target of keeping the municipal population under 23 million through 2020, achieved primarily by relocating manufacturing and lower-wage industries to surrounding cities. It worked.

As a result, Beijing today is a city whose systems are under more control than its peers — transport, healthcare, and utilities all benefit from a growing economy that has generated real investment in public services. Beijing’s per capita healthcare quality is the highest of any Chinese city, a direct consequence of that economic stabilization.

Architectural signature: Beijing’s urban structure revolves around its imperial axis — the 7.8-kilometer north-south line running through the Forbidden City, Tiananmen Square, and the Bell and Drum Towers. This historic spine is now flanked by a thoroughly modern city: the CCTV Headquarters (OMA’s radical leaning-loop structure), the Water Cube and Bird’s Nest from the 2008 Olympics, and the China Zun supertall tower define a contemporary skyline that deliberately competes with — and often consciously references — the grandeur of the imperial city it surrounds.

9. Mumbai, India — Est. Population 2026: 21,673,000

Mumbai is India’s financial capital and its most economically productive city — home to the Bombay Stock Exchange, Bollywood, and the headquarters of most of the country’s largest corporations. It is also a city built on a peninsula with an acute land shortage, which means its growth has pushed outward into the surrounding region and upward in a city already famous for its density.

The explosive growth of the past two decades — driven primarily by internal migrants seeking employment — has had a severe housing consequence. More than 40% of Mumbai’s population is estimated to live in slums, including Dharavi, one of the most densely populated urban areas in the world. These settlements are typically located far from the formal city’s job centers, creating brutal daily commutes on one of the world’s most overloaded rail systems. The Mumbai coastal road project and ongoing metro expansions are the city’s biggest recent infrastructure bets.

Architectural signature: Mumbai has one of the world’s finest collections of Victorian Gothic Revival and Art Deco architecture, much of it along the Marine Drive waterfront and the Fort district — now recognized as a UNESCO World Heritage Site. The juxtaposition of these buildings against the informal density of neighborhoods like Dharavi is one of the most architecturally jarring and humanly fascinating contrasts in any global city.

10. Osaka, Japan — Est. Population 2026: 19,059,000

A century ago, Osaka was Japan’s largest city by both area and population, its port economy driving commerce and culture across the country. Today it occupies a different but still vital role: the cultural and culinary heart of the Kansai region, defined by a personality and dialect that proudly distinguishes itself from Tokyo’s formality.

Unlike most megacities on this list, Osaka’s population has actually declined in recent decades, driven by outmigration to suburban areas and death rates that outpace birth rates — a consequence of Japan’s aging demographic challenge at the local scale. This makes Osaka something of a case study in what urban planning looks like when growth is no longer the dominant pressure: the city has focused on the quality and cultural character of its urban spaces rather than accommodating expansion.

Architectural signature: Osaka’s Dotonbori district is famous for its layered neon signage, mechanical crab and dragon sculptures, and the Glico Running Man sign — a vivid example of commercial architecture as urban spectacle. Beneath the showmanship, Osaka’s urban fabric is defined by its canal network and its short, dense blocks, creating a street life that many visitors find more navigable and human-scaled than Tokyo.

Cities 11–20: The Next Wave of Urban Giants

11. Chongqing, China — Est. 17,943,000

Perhaps the most dramatic urban landscape in China, Chongqing is built across a mountainous peninsula at the confluence of the Yangtze and Jialing rivers. Its verticality is not by architectural choice but by terrain — buildings cling to steep hillsides, and the city’s rail lines run directly through residential tower blocks. Chongqing is sometimes cited as the world’s largest city by administrative area, covering over 82,000 km², though much of that territory is rural. Its growth has been driven by China’s western development strategy, and its metro network is now one of the world’s longest.

12. Karachi, Pakistan — Est. 17,440,000

Karachi is Pakistan’s economic engine — responsible for a significant share of national GDP and federal tax revenue — yet it operates under severe infrastructure strain, with chronic water shortages, unreliable power supply, and a sprawling informal urban fabric that has grown far ahead of any formal planning. The city’s waterfront, including the recently redeveloped Karachi Expo Centre area and Sea View Promenade, represents an attempt to reclaim the city’s coastal identity. Karachi’s growth is driven by internal migration from across Pakistan and a high birth rate.

13. Kinshasa, DR Congo — Est. 17,071,000

Kinshasa is one of the fastest-growing cities in the world in absolute terms, and projections suggest it could enter the global top five by the 2060s or 2070s. Located on the south bank of the Congo River directly across from Brazzaville (the world’s closest pair of capital cities), Kinshasa’s built environment reflects its colonial history — a formal French-influenced city center surrounded by vast informal neighborhoods called cités. The challenge for Kinshasa is building urban governance capacity at a pace that can match its extraordinary demographic momentum.

14. Lagos, Nigeria — Est. 16,637,000

Lagos is Sub-Saharan Africa’s largest city and one of the fastest-growing anywhere on Earth. Its growth trajectory will likely put it among the world’s top five largest cities by mid-century. The city is known for the ambition and energy of its urban culture — and for the scale of its urban informality, with large areas of the city having developed outside any formal planning framework. The most architecturally ambitious recent project is Eko Atlantic, a 10-square-kilometer city being built on reclaimed land from the Atlantic Ocean, designed to accommodate 250,000 residents and serve as a commercial hub.

15. Istanbul, Turkey — Est. 16,047,000

Istanbul is the only major city in the world spanning two continents — its European and Asian sides connected by the Bosphorus bridges and the Marmaray rail tunnel running beneath the strait. This unique geography gives Istanbul an urban experience unlike any other: the same city looks entirely different depending on which shore you’re standing on. Its skyline blends Ottoman mosques and minarets, Byzantine walls, and contemporary glass towers. Istanbul’s growth has been sustained by internal Turkish migration and its position as a regional hub between Europe, the Middle East, and Central Asia.

16. Buenos Aires, Argentina — Est. 15,618,000

Buenos Aires is South America’s second-largest city and one of its most architecturally European — its Haussmann-inspired boulevards, Belle Époque apartment buildings, and Art Nouveau detailing earned it the nickname “the Paris of South America.” Growth here is modest and stable; Buenos Aires’ challenges are more economic than demographic, with persistent inflation and inequality shaping the city’s urban quality of life. The Puerto Madero waterfront redevelopment, transforming a derelict port into a high-density mixed-use district, is one of Latin America’s most significant urban regeneration projects.

17. Kolkata, India — Est. 15,332,000

Once the capital of British India, Kolkata retains one of the subcontinent’s richest collections of colonial-era architecture — grand Victorian public buildings, neoclassical mansions, and the iconic Howrah Bridge. But the city faces genuine challenges: its economic growth has lagged behind Mumbai, Delhi, and Bangalore for decades, leading to outmigration of skilled workers even as poorer internal migrants continue to arrive. Investment in urban infrastructure has accelerated in recent years, including extensions to the Kolkata Metro, India’s oldest rapid transit system.

18. Manila, Philippines — Est. 14,800,000

Metro Manila is one of the world’s most densely populated urban areas, with some municipalities exceeding 70,000 people per square kilometer. The city’s urban form reflects its layered history — Spanish colonial churches and plazas, American-era grid planning in districts like Ermita, and the gleaming contemporary towers of Bonifacio Global City and Makati. Traffic congestion is among the worst in the world, making infrastructure investment — particularly rail — the most urgent urban planning priority for the metropolitan region.

19. Guangzhou, China — Est. 14,512,000

Guangzhou sits at the heart of the Pearl River Delta megalopolis, a continuous urbanized region that includes Shenzhen, Foshan, Dongguan, and Hong Kong, and may collectively be the largest urban agglomeration on Earth. Guangzhou itself is known as China’s trading capital, a role it has played for over 2,000 years. Its modern architectural statement is the Canton Tower — a 600-meter twisted lattice structure completed in 2010 — which has become a symbol of the city’s contemporary ambitions.

20. Moscow, Russia — Est. 12,641,000

Moscow is Europe’s largest city, a metropolis whose urban character was permanently shaped by Soviet-era planning — wide radial boulevards, monumental Stalinist-era skyscrapers (the famous “Seven Sisters”), and the legendary Moscow Metro, whose stations are renowned globally as underground palaces of marble, mosaic, and chandeliers. The city has a sophisticated contemporary architecture scene, with significant recent development in the Moskva-City financial district and along the waterfront.

What the World’s Largest Cities Tell Us About Architecture and Urban Planning

Look at these 20 cities together and a set of architectural lessons emerges that no individual case study can provide on its own.

Verticality is a response to scarcity, not ambition. The cities with the most dramatic skylines — Tokyo, Shanghai, Mumbai, Hong Kong — are largely cities where land is genuinely limited. Height is not a lifestyle choice in these places; it’s a mathematical necessity. Cities with more available land — Karachi, Kinshasa, Lagos — tend to sprawl horizontally, which creates its own infrastructure challenges as distances between points stretch beyond what informal transport networks can bridge efficiently.

The fastest-growing cities are building informally. In Dhaka, Lagos, Manila, and Mumbai, the majority of new housing stock built over the past generation was not built by developers or governments — it was built by residents themselves, incrementally, without permits or plans. This informal urbanism is not a failure of planning; it is planning in the absence of planning. The architectural challenge for these cities is not to demolish this self-built fabric but to upgrade it — extending utilities, legalizing tenure, and adding public space — a process that requires political will as much as design expertise.

History is urban infrastructure. In Cairo, Istanbul, Mexico City, and Kolkata, the historic built environment is not a museum — it is load-bearing urban fabric that defines how people move, where they gather, and how they understand their city. Preserving, maintaining, and adaptively reusing this heritage is not sentimentality; it is one of the most economically efficient forms of urban investment available.

The next generation of megacities will be African. Lagos, Kinshasa, and Dar es Salaam will likely join the global top 10 within decades. The architectural and planning decisions being made in these cities right now — about density, land use, infrastructure systems, and public space — will shape the experience of hundreds of millions of people for a century. It is one of the most consequential design challenges on Earth, and it deserves far more attention from the global architecture community than it currently receives.

Frequently Asked Questions About the World’s Largest Cities

What is the largest city in the world by population in 2026?

Tokyo, Japan is the largest city in the world by population in 2026, with an estimated urban agglomeration of approximately 37.1 million people. However, Delhi, India is growing rapidly and is projected by the United Nations to overtake Tokyo as the world’s most populous city by around 2028 to 2030.

Will Delhi overtake Tokyo as the world’s largest city?

Yes. According to UN World Urbanization Prospects, Delhi is expected to surpass Tokyo and become the world’s most populous urban agglomeration by approximately 2028 to 2030. Delhi’s population is expanding rapidly because of high birth rates and sustained rural-to-urban migration from across India.

What is the largest city in the world by area?

By administrative area, Chongqing in China is often cited as the world’s largest city, covering over 82,000 square kilometers — though the vast majority of this territory is rural land within its administrative boundary. By continuous urban footprint, the Tokyo-Yokohama metropolitan area is the largest urbanized zone in the world.

What is a megacity?

A megacity is an urban agglomeration with a population of 10 million or more people. As of 2026, there are approximately 35 megacities worldwide, with the majority concentrated in Asia. The United Nations projects this number will continue to grow as global urbanization accelerates toward the mid-century mark.

Which continent has the most megacities?

Asia has the most megacities in the world, home to more than 20 of the world’s roughly 35 megacities as of 2026. Cities like Tokyo, Delhi, Shanghai, Dhaka, Beijing, Mumbai, and Osaka all rank among the world’s largest urban agglomerations.

What is the fastest-growing city in the world?

As of 2026, cities in Sub-Saharan Africa — particularly Lagos, Nigeria and Kinshasa in the Democratic Republic of Congo — are among the fastest-growing in the world by rate of population increase. Among the world’s top five largest cities, Delhi is growing the fastest, adding several hundred thousand residents each year.

Conclusion

The world’s largest cities are not just the biggest places on the map — they are the laboratories where humanity is working out how to live at unprecedented density, under extraordinary resource pressure, with extraordinary cultural complexity. Every skyline tells a story about how a particular society has chosen to organize itself spatially: what it values, what it fears, who it builds for, and what it leaves behind.

For architects and urban designers, the lessons embedded in these cities — from Tokyo’s transit-oriented density to Lagos’s informal self-built fabric to Cairo’s new administrative capital — are among the most important of the 21st century. The cities that navigate growth, inequality, climate risk, and infrastructure aging most successfully will be the ones that treat architecture and urban planning not as aesthetic exercises but as genuinely life-or-death public services.