Most Densely Populated Cities On Earth

Compiled by: Yan Vana

Population density is a key geographical term and a measurement of population per unit area. For example, it is commonly expressed as the number of persons per square mile or persons per square kilometer.

The world’s population density, overall, is about 41 people per square mile (8.17 billion people divided by 197 million square miles).

Cities are the most densely populated areas in the world. Those cities with very high population densities are considered to be overpopulated and are at risk of facing a lack of quality housing (or housing in general), infrastructure, and access to resources. High population density areas also face high traffic volumes and poor air quality.

The following are the 8 most densely populated cities in the world.

Manila’s 2025 population is estimated at 15,230,600. The population of the Philippines capital has grown by an estimated 288,600 in the last year, which represents a population growth of 1.93 per cent.^[1]

Pateros is a municipality of Metro Manila that covers an area of just 210 hectares (0.81 square miles).  But an estimated 2025 population of 76,460 makes this small city one of the most densely populated in the world.

Mandaluyong is a highly urbanised city in the National Capital Region of the Philippines, located directly east of Manila. The total population of Mandaluyong is estimated to be 533,000, based on a total population of 425,758 in 2020 when the last census was conducted.^[2]

Baghdad’s 2025 population is estimated at 8,141,120. The capital city of Iraq has grown by an estimated 219,990 in the last year, representing a population increase of 2.78 per cent.^[3]

Mumbai’s 2025 population is estimated at 22,089,000. Mumbai (formerly Bombay) is India’s largest city and has grown by an estimated 415,900 people in the last year, representing a 1.92 per cent population growth.^[4]

Dhaka’s 2025 population is estimated at 24,652,900. The capital city of Bangladesh has grown by an estimated 717,200 in the last year, representing a population increase of 3 per cent. Dhaka is considered to be one of the fastest growing megacities in the world.^[5]

The City of Caloocan is a highly urbanised city in Metro Manila, Philippines. According to its most recent census (2020), it has a population of 1,661,584 people making it the fourth-most populous city in the Philippines.

Port-au-Prince’s 2025 population is estimated at 3,133,080. The capital city of Haiti has grown by an estimated 72,910 in the last year, representing a population increase of 2.38 per cent.^[6] Demand for housing in Port-au-Prince is so high that hillside ‘favela-style’ developments are common. Most, however, are considered illegal as the risk of landslides is too great for them to be legally developed.

[1] World Population Review

[2] Philippine Statistics Authority

[3] United Nations: Dept of Economic and Social Affairs (Population Division) – World Population Prospects 2024

[4] World Population Review

[5] Dept of Population Sciences, University of Dhaka

[6] World Population Review

United Nations Regional Information Centre for Western Europe

The Message is the ground-breaking debut novel by Yan Vana, a thought-provoking and critically acclaimed book that will change the way you think about human overpopulation, its effects and consequences.