Philadelphia
370 km²
Seoul
605 km²
United States
South Korea
Area Comparison
Philadelphia is 1.6x smaller than Seoul
Population Comparison
Philadelphia has 6.1x fewer people than Seoul
Seoul is significantly larger, covering 1.6 times the area of Philadelphia. Seoul spans 605 km² (234 mi²) while Philadelphia covers 370 km² (143 mi²) — a difference of 235 km².
To put Philadelphia's size in perspective, its area of 370 km² is about 1.6x smaller than Seoul. Meanwhile, Seoul at 605 km² is about 1.3x smaller than New York City.
In more relatable units, Philadelphia's 370 km² is about 52,000 American football fields, 180 times the area of Monaco, or 110 times the area of Central Park. Seoul, by comparison, equals about 85,000 American football fields, 180 times the area of Central Park, or 10 times the area of Manhattan.
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.
Known as "Philly", Philadelphia covers 370 km² with a population of 1.6 million. The city was established in 1682. Philadelphia is known for Liberty Bell, Independence Hall, Philly Cheesesteak, among other attractions.
Philadelphia is the sixth-most populous US city, with an estimated 1,574,281 residents as of July 2025.
Seoul, officially Seoul Special Metropolitan City, is the capital and largest city of South Korea, and the largest city in the whole of Korea. The broader Seoul Metropolitan Area, encompassing Seoul, Gyeonggi Province and Incheon, emerged as the world's sixth largest metropolitan economy in 2022, behind New York, Tokyo, Los Angeles, Paris, and London, and hosts more than half of South Korea's population.
Seoul has an area of 605 km² and is home to 9.8 million people. Its history stretches back to 18 BC. Visitors come for Gyeongbokgung Palace, Gangnam district, Myeongdong shopping, and much more. Getting around is easy with the Seoul Metro.
Seoul Metropolitan Area emerged as the world's sixth largest metropolitan economy in 2022, behind only NYC, Tokyo, LA, Paris, and London.
Philadelphia has a population density of 4,324 people per km² — a moderately dense city. Seoul, with 16,149 people per km², is an extremely dense urban environment. Seoul is dramatically more crowded, with 3.7x the population density.
Density Gap
Seoul is 3.7x more densely populated
History
Seoul is ~1,700 years older
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).
Seoul covers 605 km². Cities with a similar urban footprint include Chicago (606 km²), Madrid (604 km²), Mumbai (603 km²), Toronto (630 km²), or Hyderabad (650 km²).
The straight-line distance from Philadelphia to Seoul is 11,104 km (6,900 miles), with an estimated flight time of ~13h 34m.
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