Nairobi
696 km²
Philadelphia
370 km²
Kenya
United States
Area Comparison
Nairobi is 1.9x larger than Philadelphia
Population Comparison
Nairobi has 3.0x more people than Philadelphia
Nairobi is significantly larger, covering 1.9 times the area of Philadelphia. Nairobi spans 696 km² (269 mi²) while Philadelphia covers 370 km² (143 mi²) — a difference of 326 km².
To put Nairobi's size in perspective, its area of 696 km² is about 1.1x smaller than New York City. Meanwhile, Philadelphia at 370 km² is about 1.6x smaller than Seoul.
Nairobi's footprint is roughly about 97,000 American football fields, 12 times the area of Manhattan, or 7 times the area of Paris — pick whichever unit feels intuitive. Philadelphia, by comparison, equals about 52,000 American football fields, 180 times the area of Monaco, or 110 times the area of Central Park.
Nairobi is the capital and largest city of Kenya, located in the south-central part of the country. As of 2024, it has a population of 4.8 million and a metropolitan population of 5.7 million, making it the 11th most populous city in Africa. Nicknamed the "Green City under the Sun", Nairobi is uniquely notable for being the only capital city in the world that hosts a national park within its boundaries. Its name originates from the Maasai phrase Enkare Nyirobi, meaning "place of cool waters".
Known as "Green City under the Sun", Nairobi covers 696 km² with a population of 4.7 million. The city was established in 1899. Nairobi is known for Nairobi National Park, Giraffe Centre, Karen Blixen Museum, among other attractions. The city's main transit system is the Nairobi Commuter Rail.
Nairobi is the only capital city in the world that hosts a national park within its boundaries.
Philadelphia, colloquially referred to as Philly, is the most populous city in the U.S. state of Pennsylvania, and the sixth-most populous city in the United States, with a Census-estimated population of 1,574,281 in July 2025. The Philadelphia metropolitan area has 6.33 million residents and is the nation's ninth-largest metropolitan area. Philadelphia is known for its culture, cuisine, and history, maintaining contemporary influence in business and technology, sports, and music.
Also known as "Philly", Philadelphia has an area of 370 km² and is home to 1.6 million people. Its history stretches back to 1682. Visitors come for Liberty Bell, Independence Hall, Philly Cheesesteak, and much more.
Philadelphia is the sixth-most populous US city, with an estimated 1,574,281 residents as of July 2025.
Nairobi has a population density of 6,796 people per km² — a densely populated city. Philadelphia, with 4,324 people per km², is a moderately dense city. Nairobi is noticeably denser, packing 1.6 times more people per square kilometer.
Density Gap
Nairobi is 1.6x more densely populated
History
Philadelphia is ~217 years older
Nairobi covers 696 km². Cities with a similar urban footprint include Tehran (730 km²), Jakarta (662 km²), Singapore (733 km²), Bangalore (741 km²), or Hyderabad (650 km²).
Philadelphia covers 370 km². Cities with a similar urban footprint include Seattle (369 km²), Dhaka (368 km²), Portland (376 km²), Atlanta (348 km²), or Denver (401 km²).
The straight-line distance from Nairobi to Philadelphia is 11,958 km (7,430 miles), with an estimated flight time of ~14h 34m.
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