Seoul
605 km²
Sydney
12,368 km²
South Korea
Australia
Area Comparison
Seoul is 20.4x smaller than Sydney
Population Comparison
Seoul has 1.8x more people than Sydney
In terms of area, Sydney is 20.4x the size of Seoul. Sydney spans 12,368 km² (4,775 mi²) while Seoul covers 605 km² (234 mi²) — a difference of 11,763 km². You could fit Seoul inside Sydney approximately 20 times.
To put Seoul's size in perspective, its area of 605 km² is about 1.3x smaller than New York City. Meanwhile, Sydney at 12,368 km² is about 2.0x the size of Shanghai.
Seoul's footprint is roughly about 85,000 American football fields, 180 times the area of Central Park, or 10 times the area of Manhattan — 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.
Seoul, officially Seoul Special Metropolitan City, is the capital and largest city of South Korea, and the largest city in the whole of Korea. The broader Seoul Metropolitan Area, encompassing Seoul, Gyeonggi Province and Incheon, emerged as the world's sixth largest metropolitan economy in 2022, behind New York, Tokyo, Los Angeles, Paris, and London, and hosts more than half of South Korea's population.
Seoul covers 605 km² with a population of 9.8 million. The city was founded around 18 BC. Seoul is known for Gyeongbokgung Palace, Gangnam district, Myeongdong shopping, among other attractions. The city's main transit system is the Seoul Metro.
Seoul Metropolitan Area emerged as the world's sixth largest metropolitan economy in 2022, behind only NYC, Tokyo, LA, Paris, and London.
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.
Looking beyond city limits, the Sydney metropolitan area covers 12,368 km², which is 1.1x larger than greater Seoul at 11,704 km². The Seoul metro area is also more populous, with 25.5 million people compared to 5.3 million.
Seoul has a population density of 16,149 people per km² — an extremely dense urban environment. Sydney, with 429 people per km², is a low-density, sprawling urban area. Seoul is dramatically more crowded, with 37.6x the population density.
This comparison spans continents — Seoul in Asia versus Sydney in Oceania. Despite the geographic distance, comparing their sizes reveals surprising insights about how cities grow worldwide.
Seoul has a humid continental climate while Sydney experiences humid subtropical conditions. Winters differ dramatically: Sydney stays around 13°C while Seoul drops to -3°C.
Size Ratio
Seoul fits inside Sydney ~20 times
Density Gap
Seoul is 37.6x more densely populated
History
Seoul is ~1,806 years older
Seoul covers 605 km². Cities with a similar urban footprint include Chicago (606 km²), Madrid (604 km²), Mumbai (603 km²), Toronto (630 km²), or Hyderabad (650 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 Seoul to Sydney is 8,329 km (5,176 miles), with an estimated flight time of ~10h 18m.
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