Hanoi
3,359 km²
Philadelphia
370 km²
Vietnam
United States
Area Comparison
Hanoi is 9.1x larger than Philadelphia
Population Comparison
Hanoi has 5.0x more people than Philadelphia
Hanoi is significantly larger, covering 9.1 times the area of Philadelphia. Hanoi spans 3,359 km² (1,297 mi²) while Philadelphia covers 370 km² (143 mi²) — a difference of 2,989 km². You could fit Philadelphia inside Hanoi approximately 9 times.
To put Hanoi's size in perspective, its area of 3,359 km² is about 1.2x smaller than Rhode Island. Meanwhile, Philadelphia at 370 km² is about 1.6x smaller than Seoul.
Picture Hanoi another way: its area is large enough to fit about 470,000 American football fields, 57 times the area of Manhattan, or 32 times the area of Paris. Philadelphia, by comparison, equals about 52,000 American football fields, 180 times the area of Monaco, or 110 times the area of Central Park.
Hanoi is the capital and second-most populous municipality of Vietnam. It encompasses an area of 3,358.6 km2 (1,296.8 mi2), and as of 2025 has a population of 8,807,523. Hanoi had the second-highest gross regional domestic product of all Vietnamese provinces and municipalities at US$48 billion in 2023, behind Ho Chi Minh City. It hosts 78 foreign embassies, the headquarters of the Vietnam People's Army (VPA), its Vietnam National University system, and other governmental organizations.
Known as "City Between Rivers", Hanoi covers 3,359 km² with a population of 8.1 million. The city was established in 1010. Hanoi is known for Hoan Kiem Lake, Old Quarter, Temple of Literature, among other attractions. The city's main transit system is the Hanoi Metro.
Hanoi encompasses 3,358.6 square kilometers and had a population of nearly 8.8 million as of 2025.
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.
Hanoi has a population density of 2,397 people per km² — a moderately dense city. Philadelphia, with 4,324 people per km², is a moderately dense city. Philadelphia is noticeably denser, packing 1.8 times more people per square kilometer.
Size Ratio
Philadelphia fits inside Hanoi ~9 times
Density Gap
Philadelphia is 1.8x more densely populated
History
Hanoi is ~672 years older
Hanoi covers 3,359 km². Cities with a similar urban footprint include Karachi (3,527 km²), Cairo (3,085 km²), Dubai (4,114 km²), Lima (2,672 km²), or Moscow (2,511 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 Hanoi to Philadelphia is 13,234 km (8,223 miles), with an estimated flight time of ~16h 4m.
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