Hanoi
3,359 km²
Houston
1,725 km²
Vietnam
United States
Area Comparison
Hanoi is 1.9x larger than Houston
Population Comparison
Hanoi has 3.5x more people than Houston
In terms of area, Hanoi is 1.9x the size of Houston. Hanoi spans 3,359 km² (1,297 mi²) while Houston covers 1,725 km² (666 mi²) — a difference of 1,634 km².
To put Hanoi's size in perspective, its area of 3,359 km² is about 1.2x smaller than Rhode Island. Meanwhile, Houston at 1,725 km² is roughly the same size as London.
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. For Houston, that's about 242,000 American football fields, 29 times the area of Manhattan, or 16 times the area of Paris.
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.
Houston is the most populous city in the U.S. state of Texas and the Southern United States. It is the fourth-most populous city in the United States, with a population of 2.3 million at the 2020 census. The Greater Houston metropolitan area, at 7.8 million residents, is the fifth-most populous metropolitan area in the nation and second-most populous in Texas. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, Houston is the county seat of Harris County.
Nicknamed "Space City", Houston has an area of 1,725 km² and is home to 2.3 million people. Its history stretches back to 1836. Visitors come for NASA Johnson Space Center, Space Center Houston, Houston Astros, and much more.
Houston is the fourth-most populous US city with 2.3 million residents at the 2020 census, leading the entire South.
Hanoi has a population density of 2,397 people per km² — a moderately dense city. Houston, with 1,333 people per km², is a relatively spread-out city. Hanoi is noticeably denser, packing 1.8 times more people per square kilometer.
Density Gap
Hanoi is 1.8x more densely populated
History
Hanoi is ~826 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).
Houston covers 1,725 km². Cities with a similar urban footprint include Riyadh (1,798 km²), Johannesburg (1,644 km²), Bogotá (1,578 km²), London (1,572 km²), or Bangkok (1,569 km²).
The straight-line distance from Hanoi to Houston is 13,929 km (8,655 miles), with an estimated flight time of ~16h 53m.
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