Sydney vs Seoul
Sydney is about 20× larger than Seoul by administrative area. Sydney (Australia) covers 12,145 km² (4,689 mi²) with a population of 5.5 million, while Seoul (South Korea) covers 605 km² (234 mi²) with 9.7 million residents.
| Metric | Sydney | Seoul |
|---|---|---|
| Area | 12,145 km² | 605 km² |
| Area (mi²) | 4,689 mi² | 234 mi² |
| Population | 5,450,496 | 9,668,465 |
| Population density | 449 /km² | 15,974 /km² |
| Area ratio | Sydney is ~20× larger by area than Seoul. | |
Frequently asked questions
Is Sydney bigger than Seoul?
Yes — Sydney is about 20× larger by area: 12,145 km² vs 605 km².
How big is Sydney?
Sydney, Australia, covers about 12,145 km² (4,689 mi²) of administrative area.
How big is Seoul?
Seoul, South Korea, covers about 605 km² (234 mi²) of administrative area.
Which city has more people, Sydney or Seoul?
Seoul has the larger population: 9.7 million vs 5.5 million. Population density is about 449 people/km² in Sydney and 15,974 people/km² in Seoul.
City boundaries from OpenStreetMap. Last updated 2026-08-18.
Compare other cities on the map