Osaka
225 km²
San Diego
964 km²
Japan
United States
Area Comparison
Osaka is 4.3x smaller than San Diego
Population Comparison
Osaka has 2.0x more people than San Diego
In terms of area, San Diego is 4.3x the size of Osaka. San Diego spans 964 km² (372 mi²) while Osaka covers 225 km² (87 mi²) — a difference of 739 km². You could fit Osaka inside San Diego approximately 4 times.
To put Osaka's size in perspective, its area of 225 km² is roughly the same size as Amsterdam. Meanwhile, San Diego at 964 km² is roughly the same size as Berlin.
Osaka's footprint is roughly about 32,000 American football fields, 110 times the area of Monaco, or 66 times the area of Central Park — pick whichever unit feels intuitive. San Diego, by comparison, equals about 135,000 American football fields, 16 times the area of Manhattan, or 9 times the area of Paris.
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…
Known as "Nation's Kitchen", Osaka covers 225 km² with a population of 2.8 million. The city was established in 645. Osaka is known for Osaka Castle, Dotonbori district, Universal Studios Japan, among other attractions. The city's main transit system is the Osaka Metro.
Osaka is the third-most populous city in Japan, following the special wards of Tokyo and Yokohama.
San Diego is a city on the Pacific coast of Southern California, adjacent to the Mexico–United States border. It is the eighth-most populous city in the U.S. and second-most populous city in California with a population of over 1.4 million, while the San Diego metropolitan area with over 3.3 million residents is the 18th-largest metropolitan area in the country. San Diego is the county seat of San Diego County.
Nicknamed "America's Finest City", San Diego has an area of 964 km² and is home to 1.4 million people. The city dates back to 1769. Visitors come for San Diego Zoo, Balboa Park, Coronado Beach, and much more.
San Diego sits directly on the Mexico-United States border, making it California's southwesternmost major city.
Osaka has a population density of 12,222 people per km² — an extremely dense urban environment. San Diego, with 1,442 people per km², is a relatively spread-out city. Osaka is dramatically more crowded, with 8.5x the population density.
Size Ratio
Osaka fits inside San Diego ~4 times
Density Gap
Osaka is 8.5x more densely populated
History
Osaka is ~1,124 years older
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).
San Diego covers 964 km². Cities with a similar urban footprint include Abu Dhabi (972 km²), Dallas (997 km²), Berlin (892 km²), Santiago (838 km²), or Hong Kong (1,114 km²).
The straight-line distance from Osaka to San Diego is 9,360 km (5,816 miles), with an estimated flight time of ~11h 31m.
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