Perth
6,417 km²
San Diego
964 km²
Australia
United States
Area Comparison
Perth is 6.7x larger than San Diego
Population Comparison
Perth has 1.5x more people than San Diego
Yes — Perth is 6.7x larger than San Diego by area. Perth spans 6,417 km² (2,478 mi²) while San Diego covers 964 km² (372 mi²) — a difference of 5,453 km². You could fit San Diego inside Perth approximately 6 times.
To put Perth's size in perspective, its area of 6,417 km² is roughly the same size as Shanghai. Meanwhile, San Diego at 964 km² is roughly the same size as Berlin.
Perth's footprint is roughly about 899,000 American football fields, 110 times the area of Manhattan, or 61 times the area of Paris — pick whichever unit feels intuitive. San Diego works out to about 135,000 American football fields, 16 times the area of Manhattan, or 9 times the area of Paris.
Perth is the capital city of Western Australia. It is the fourth-most-populous city in Australia, with a population of over 2.3 million within Greater Perth as of 2023. The world's most isolated major city by certain criteria, Perth is part of the South West Land Division of Western Australia, with most of Perth's metropolitan area on the Swan Coastal Plain between the Indian Ocean and the Darling Scarp.
Known as "City of Light", Perth covers 6,417 km² with a population of 2.1 million. The city was established in 1829. Perth is known for Swan River, Kings Park, Cottesloe Beach, among other attractions.
Perth is considered the world's most isolated major city by certain criteria, sitting on Australia's west coast.
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.
Often called "America's Finest City", San Diego has an area of 964 km² and is home to 1.4 million people. Its history stretches 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.
Perth has a population density of 333 people per km² — a low-density, sprawling urban area. San Diego, with 1,442 people per km², is a relatively spread-out city. San Diego is dramatically more crowded, with 4.3x the population density.
Size Ratio
San Diego fits inside Perth ~6 times
Density Gap
San Diego is 4.3x more densely populated
Perth covers 6,417 km². Cities with a similar urban footprint include Shanghai (6,341 km²), Guangzhou (7,434 km²), Istanbul (5,461 km²), Wuhan (8,569 km²), or Melbourne (9,993 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 Perth to San Diego is 15,087 km (9,375 miles), with an estimated flight time of ~18h 15m.
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