San Diego
964 km²
Sydney
12,368 km²
United States
Australia
Area Comparison
San Diego is 12.8x smaller than Sydney
Population Comparison
San Diego has 3.8x fewer people than Sydney
Sydney is significantly larger, covering 12.8 times the area of San Diego. Sydney spans 12,368 km² (4,775 mi²) while San Diego covers 964 km² (372 mi²) — a difference of 11,404 km². You could fit San Diego inside Sydney approximately 12 times.
To put San Diego's size in perspective, its area of 964 km² is roughly the same size as Berlin. Meanwhile, Sydney at 12,368 km² is about 2.0x the size of Shanghai.
San Diego's footprint is roughly about 135,000 American football fields, 16 times the area of Manhattan, or 9 times the area of Paris — pick whichever unit feels intuitive. For Sydney, that's about 1,700,000 American football fields, 120 times the area of Paris, or 100 times the area of San Francisco.
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.
Known as "America's Finest City", San Diego covers 964 km² with a population of 1.4 million. The city was established in 1769. San Diego is known for San Diego Zoo, Balboa Park, Coronado Beach, among other attractions.
San Diego sits directly on the Mexico-United States border, making it California's southwesternmost major city.
Sydney is the capital city of the state of New South Wales, and is the most populous city in Australia. Located on Australia's east coast, the metropolis surrounds Sydney Harbour and extends about 80 kilometres (50 mi) from the Pacific Ocean in the east to the Blue Mountains in the west, and about 80 kilometres (50 mi) from Ku-ring-gai Chase National Park and the Hawkesbury River in the north and north-west, to the Royal National Park and Macarthur in the south and south-west.
Nicknamed "Sydneysiders", Sydney has an area of 12,368 km² and is home to 5.3 million people. It was established in 1788. Visitors come for Sydney Opera House, Sydney Harbour Bridge, Bondi Beach, and much more. Getting around is easy with the Sydney Trains.
Sydney stretches roughly 80 km from the Pacific Ocean in the east to the Blue Mountains in the west.
San Diego has a population density of 1,442 people per km² — a relatively spread-out city. Sydney, with 429 people per km², is a low-density, sprawling urban area. San Diego is dramatically more crowded, with 3.4x the population density.
Size Ratio
San Diego fits inside Sydney ~12 times
Density Gap
San Diego is 3.4x more densely populated
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).
Sydney covers 12,368 km². Cities with a similar urban footprint include Chengdu (14,378 km²), Xi'an (10,097 km²), Melbourne (9,993 km²), Brisbane (15,826 km²), or Beijing (16,411 km²).
The straight-line distance from San Diego to Sydney is 12,090 km (7,512 miles), with an estimated flight time of ~14h 43m.
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