Hanoi
3,359 km²
Osaka
225 km²
Vietnam
Japan
Area Comparison
Hanoi is 14.9x larger than Osaka
Population Comparison
Hanoi has 2.9x more people than Osaka
Yes — Hanoi is 14.9x larger than Osaka by area. Hanoi spans 3,359 km² (1,297 mi²) while Osaka covers 225 km² (87 mi²) — a difference of 3,134 km². You could fit Osaka inside Hanoi approximately 14 times.
To put Hanoi's size in perspective, its area of 3,359 km² is about 1.2x smaller than Rhode Island. Meanwhile, Osaka at 225 km² is roughly the same size as Amsterdam.
In more relatable units, Hanoi's 3,359 km² is about 470,000 American football fields, 57 times the area of Manhattan, or 32 times the area of Paris. Osaka, by comparison, equals about 32,000 American football fields, 110 times the area of Monaco, or 66 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.
Osaka is a designated city in the Kansai region of Honshu in Japan. It is the capital of and most populous city in Osaka Prefecture, and the third-most populous city in Japan, following the special wards of Tokyo and Yokohama. With an estimated population of 2,816,247 as of October 1, 2025 and a population density of about 12,505 people per square kilometer, it is the largest component of the Keihanshin Metropolitan Area, the second-largest metropolitan area in Japan and the 10th-largest urban…
Nicknamed "Nation's Kitchen", Osaka has an area of 225 km² and is home to 2.8 million people. It was established in 645. Visitors come for Osaka Castle, Dotonbori district, Universal Studios Japan, and much more. Getting around is easy with the Osaka Metro.
Osaka is the third-most populous city in Japan, following the special wards of Tokyo and Yokohama.
Looking beyond city limits, the Osaka metropolitan area covers 13,228 km², which is 3.9x larger than greater Hanoi at 3,359 km². The Osaka metro area is also more populous, with 19.3 million people compared to 8.1 million.
Hanoi has a population density of 2,397 people per km² — a moderately dense city. Osaka, with 12,222 people per km², is an extremely dense urban environment. Osaka is dramatically more crowded, with 5.1x the population density.
Both cities are in Asia, but they represent different national approaches to urban development. Hanoi (Vietnam) and Osaka (Japan) offer a fascinating regional contrast.
Both cities share a humid subtropical climate, though local geography creates distinct microclimates in each. When it's noon in Osaka, it's 10:00 AM in Hanoi — a 2-hour time difference.
Size Ratio
Osaka fits inside Hanoi ~14 times
Density Gap
Osaka is 5.1x more densely populated
History
Osaka is ~365 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).
Osaka covers 225 km². Cities with a similar urban footprint include Amsterdam (219 km²), Boston (232 km²), Helsinki (214 km²), Kuala Lumpur (243 km²), or Buenos Aires (203 km²).
The straight-line distance from Hanoi to Osaka is 3,271 km (2,032 miles), with an estimated flight time of ~4h 21m.
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