The largest city in the world is Tokyo, Japan, with a total population of 37 million people. With a population density of 2,642 persons per square kilometre, it is also one of the most densely populated cities on Earth.
Here are the 14 most populated cities on Earth, and what it is like to live in them. To put this list of biggest cities into perspective, the population of Greater London, UK, is 8.9 million, and New York City, USA, is approximately 8 million.
| Rank | City | Country | Total population (millions) |
|---|---|---|---|
| 1 | Tokyo | Japan | 37.4 |
| 2 | Delhi | India | 29.3 |
| 3 | Shanghai | China | 26.3 |
| 4 | São Paulo | Brazil | 21.8 |
| 5 | Mexico City | Mexico | 21.6 |
| 6 | Cairo | Egypt | 20.4 |
| 7 | Dhaka | Bangladesh | 20.2 |
| 8 | Mumbai | India | 20.1 |
| 9 | Beijing | China | 19.4 |
| 10 | Osaka | Japan | 19.2 |
| 11 | Chongqing | China | 17.8 |
| 12 | Karachi | Pakistan | 17.6 |
| 13 | Kinshasa | Democratic Republic of the Congo | 17 |
| 14 | Lagos | Nigeria | 16.5 |
Just how many people could live in Tokyo’s metropolis, and in other mega-cities around the planet? Well, the global population is currently eight billion and counting, growing by about 0.87 per cent a year – that’s around 71 million people.
However, some studies suggest that the world population will peak at 8.8 billion people by the middle of this century before it starts to decline. Other predictions, such as those made by the United Nations, estimate that the world's population could hit 9.7 billion in 2050 and 10.9 billion in 2100.
In any case, the substantial increase in population has led to significant congestion in several of the world’s largest cities, giving rise to major concerns regarding pollution and overcrowding. And they’re set to keep growing – by 2050, the UN estimates that about 66 per cent of the world population will be living in cities. It is also estimated that by 2030, the world could have 43 so-called megacities (up from 31 today, according to reports) – those with more than 10 million inhabitants.
In full, here are the 14 most-populated cities on Earth, and what it is like to live in them.
14. Lagos, Nigeria – 16.5 million people
This fast-growing, energetic and noisy Nigerian city on the coast of the Gulf of Guinea is a vibrant place of rich cultural heritage, festivals, bustling markets and beaches. Lagos is dominated by the Yorubas but contains residents hailing from almost every ethnic group in Nigeria.
As it sprawls across Lagos Lagoon, part of this megacity is a floating fishing community in the Makoko area, with many of the properties built on stilts. As the population has grown, however, pollution and overcrowding have become a problem, and the water today is heavily polluted with rubbish and sewage.
Elsewhere in Lagos, the city has been expanding recently on Victoria Island with construction on 10 million m² of land reclaimed from the Atlantic in an attempt to make more room for the growing population. Eko Atlantic City is expected to house 250,000 inhabitants and have an imposing skyline of towers housing businesses and hotels.
13. Kinshasa, Democratic Republic of the Congo – 17 million people
The capital of the Democratic Republic of the Congo, Kinshasa is a rapidly expanding city, as people migrate there from rural areas, and currently has just over 17 million inhabitants. It sits on the south bank of the Congo River and has both extreme poverty and excessive wealth, with housing comprising high-rise apartments and luxurious villas but mostly sprawling communities living in tin-roofed concrete-block houses in squatting zones.
The country has been gripped by political turmoil since the downfall of the Zairean regime in 1997, which has left a difficult economic situation in Kinshasa, and the rapid growth of the city has created serious problems regarding food supply.
The city has a rich music history and is known for Soukous, a guitar-driven dance music with Cuban origins.
12. Karachi, Pakistan - 17.6 million people
Once a small fishing village in the early 18th century, Karachi, on the Arabian Sea coast, is Pakistan’s business and industrial hub and is today one of the world’s megacities with a population of 17.6 million people.
A huge influx of job-seeking immigrants from rural areas nearly doubled the city’s size at the end of the 20th century, with most forced to live in urban shantytowns known as katchi abadis. More recently, the city has filled with tens of thousands of Afghan refugees.
Violence and crime between ethnic factions have plagued this city, and infrastructure and sanitation are still a problem. This year, Karachi also suffered deadly heatwaves – not an easy thing to deal with when so many people are packed together. And the city is expected to continue to swell as the impacts of climate change, such as the major flooding in August 2024, affect Pakistan. It is predicted that Karachi could receive as many as 2.3 million domestic climate migrants by 2050
11. Chongqing, China - 17.8 million people
Millions of people have migrated to Chongqing in the last few decades, looking for a better life, which means the city has grown and grown, swelling to almost double its size and becoming one of the largest cities in the world. This megalopolis, a former trading centre on the Yangtze, today has 17.8 million inhabitants.
Due to its burgeoning population, this thronging, dazzling city had a hard time managing its pollution and waste, with terrible air quality, hazy skies, and giant rubbish pits in its surrounding hills, but now efforts are being made to make Chongqing a ‘zero-waste’ city.
Some districts now have smart waste sorting facilities with automated systems, which means residents can put out their recyclables, food waste, and rubbish without touching the bins.
10. Osaka, Japan - 19.2 million people
Keihanshin Metropolitan Area, which includes Japan's third-largest city Osaka, is home to some 19.2 million people. Historically important as a centre of commerce and industry, the city is still a financial hub home to many large Japanese companies.
Osaka is famed for its food culture and modern architecture, making it popular with tourists. And thanks to a half-decent public transport system that would be unheard of in the UK, the city's Metro manages to carry over 900 million people a year.
It is not all good news though. As with any modern megacity, traffic is a huge issue thanks to overcrowded roads, and decent housing is hard to find... even if you have tonnes of cash.
9. Beijing, China - 19.4 million people
China's second-largest city is one of the oldest cities in the world, and is also home to most of the country's biggest businesses. This has led to huge population growth in the last 50 years, and increasing wealth amongst many of its residents. In fact, Beijing now has the most number of billionaires in world.
However, it's not all good news. Thanks to a combination of industrial pollution, frequent sandstorms and car emissions, many residents in Beijing are often told to stay indoors to avoid the potential health hazards.
Car use has increased massively over the last ten years, despite an impressive subway system and various bicycle loan projects.
And with a population density of 4,600 people per km, the residents of Beijing probably find it hard to get a moment to themselves.
8. Mumbai, India - 20.1 million people
Mumbai is built on seven islands, and is an historic city that is full of culture and art. It is also home to the Indian film industry (Bollywood), known around the world for its vibrant movies and musical numbers.
Most importantly, it is the commercial and financial capital of India. Most of the largest companies in India are based in Mumbai, which has led to a huge influx of people from rural areas wanting to live there.
This naturally causes some headaches, with poor sanitation and low-quality housing being the main problems. Mumbai also has some of the world’s busiest roads, mainly due to a lack of high-capacity infrastructure and a public transport system that is unable to cope with demand.
7. Dhaka, Bangladesh - 20.2 million people
The capital city of Bangladesh is growing at a fast rate, which is fuelled in part by a thriving publishing industry. This has led to vast high-rise apartments and offices sprouting up all over this sprawling metropolis.
This historic city is the centre of Bengali culture, hosting countless art festivals and religious events throughout the year. It is also home to the government of Bangladesh, as well as historic buildings such as the Nimtali Palace and the Lalbagh Fort.
However, due to its position on the Ganges Delta, Dhaka is somewhat prone to flooding during the monsoon and cyclone seasons.
6. Cairo, Egypt - 20.4 million people
In addition to its historically significant architecture, Cairo is probably best known as the home of one of the ancient wonders of the world; the ancient Egyptian Giza pyramid complex. It is also home to 11 per cent of the population of Egypt.
There are plans in place to build two monorail systems to serve the city, which will help to ease the significant traffic issues that the city currently experiences.
Frequent dust storms and the desert climate might sound like a deterrent, but this doesn’t stop people wanting to visit…
5. Mexico City, Mexico - 21.6 million people
Mexico City sits high on the plateau known as the Valley of Mexico, 2,240m above sea level, and is the oldest capital city in the Americas.
The growth of this metropolis is remarkable. In 1900, its population stood at a mere 500,000 people. But due to large numbers of people from rural areas coming to the city looking for work, this ballooned to nine million by the 1970s. Because of a lack of housing, this influx led to large numbers of people setting up illegal shantytowns around the city.
Mexico City is now a centre of business and also a popular tourist attraction, full of museums and places to eat. Amazingly, if Mexico City were an independent country, it would be the fifth-largest economy in South America.
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4. São Paulo, Brazil - 21.8 million people
It is a bit of a cliché, but São Paulo is a city of huge contrast. A place where extreme poverty meets great wealth, with the biggest skyscrapers of the financial district towering over the slums of the city, known as the favelas.
Water supply issues are a problem in São Paulo, with few natural sources of drinking water in the city. The haphazard nature of the layout of the city and its buildings doesn't help.
However, crime has been falling and air quality has been steadily improving in recent years, making it a nicer place to live for all of its 22 million residents.
3. Shanghai, China - 26.3 million people
Many many years ago, Shanghai used to be a small fishing village. But thanks to its location by the southern estuary of the Yangtze River, it has since grown to be the biggest city in China, and one of the largest in the world.
It is also home to the Nanjing Road shopping district, a mix of modern malls and traditional Chinese stores and food outlets. Its 5.5km streets rank alongside Oxford Street in London and the Champs-Élysées in Paris as one of the busiest commercial areas in the world, with one million people shopping there every day.
2. Delhi, India - 29.3 million people
The National Capital Territory of Delhi (NCT) encompasses the city of New Delhi (the nation's capital), as well as several other regional states.
The city itself has been in existence for over 2,000 years, which brings its own set of problems. Infrastructure is outdated, although there have been many recent road-building projects that have helped to ease traffic.
Pollution from roads and industry is also a big problem in Delhi, as is the standard of housing. It is estimated that 50 per cent of the population live in sub-standard accommodation.
1. Tokyo, Japan - 37.4 million people
Tokyo, Japan, is the largest city on Earth, with a population of 37.4 million people, which is over four times the population of New York City, USA. In total, the Japanese metropolis covers an area of 13,452km2.
There are 2,642 people in each km on average in the whole of the Greater Tokyo Area. This high density obviously presents problems for its residents in terms of living space and travel.
As to be expected, housing shortages are widespread. Because of this, tiny apartments that measure only 9m2 are becoming increasingly popular amongst younger residents, as they try to locate themselves near the centre of the city for work.
Getting around the city is very problematic too. The roads are often completely packed in and around the city. Public transport is also often overcrowded and expensive, although it is almost always on schedule.
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