Place comparison
Seoul compared with Taipei City: area, population and density
Seoul covers roughly 2.2 times Taipei City’s land area and holds close to four times its residents, so its average density is well above Taipei’s.
Equal-area outline comparison
Outlines are centered and scaled by official land area; position does not show geographic location.
Area
Population
Population density
Area data date
Population data date
:
:
The guide below belongs to this pair: Seoul and Taipei City. Change the selector above and the page follows, so the reading always matches the tool.
Direct answer
How different are Seoul and Taipei City?
Seoul covers 605.2 km²; Seoul's area is 2.23 times Taipei City's. Its reported population is 9,335,444; Seoul's population is 3.83 times Taipei City's. By average density, Seoul's population density is 1.72 times Taipei City's.
Population difference
Seoul's population is 3.83 times Taipei City's 9,335,444 · 2,439,507Density difference
Seoul's population density is 1.72 times Taipei City's 15,425.4 /km² · 8,975.4 /km²Full data and sources for each place: Seoul, Taipei City
Straight-line distance between geometric centres: about 1479 km; time difference: 1 hours.
On a familiar scale
- Seoul ≈ 56% of Changhua County (reference rung) 65 m² of land per resident
- Taipei City ≈ 1.79 × Kinmen County (reference rung) 111 m² of land per resident
Reference scales come from Department of Household Registration, Ministry of the Interior: Land area, households and population density by township and district (year-end 2025) , as of 2025-12-31.
How to read it
Population differs by more than area does, which is why Seoul is the denser of the two despite both being compact capital cities.
Geography and shape
Both cities sit in river basins ringed by hills: Seoul along the Han River, Taipei in a basin drained by the Tamsui River system. Each administrative boundary therefore includes uplands that carry very few residents, so neither outline is a map of built-up ground.
Population context
Seoul’s population is close to four times Taipei City’s while its land is about 2.2 times as large, so the average density gap is roughly 1.7 times. Both figures are city-proper counts and exclude the far larger metropolitan regions around each city.
Boundaries and definitions
Seoul Special City and Taipei City are both city-level administrative units, which makes this an unusually clean pair on this site. The dates and population systems still differ: Seoul uses a register-based census, Taipei uses household registration at year-end 2025. Household registration counts where people are registered, not where they sleep.
Seoul: Seoul Special City, the 25-district city government of 605.2 km². It is not the Seoul Capital Area, the commuter region of Seoul, Incheon and Gyeonggi Province, which is roughly twenty times larger and holds about 26.3 million people. Population is the 2024 register-based census total: everyone usually resident inside the city boundary on 1 November 2024, including 367,291 foreign residents, which is a different universe from the resident-registration series readers may know. Area is registered cadastral land at 31 December 2024, summed from the ministry's parcel-level file because no single line publishes the city total; the same method reproduces South Korea's national figure exactly. The two reference dates are two months apart.
Taipei City: Taipei City, the special municipality alone. Area and registered population come from the same Ministry of the Interior table at the same year-end 2025 reference date, so the density is like for like. The figure excludes New Taipei City: “Taipei” in everyday speech often means the two cities together (2,324.3664 km², 6,484,338 residents) or the wider metropolitan area, which has no single official boundary. Population is household registration, not resident presence.
In-depth guide
How should Seoul and Taipei City be understood in context?
This is the cleanest pairing on the site: two city-level administrations, each measured as the city itself rather than the region around it. Seoul is about 2.2 times Taipei City by area and close to four times by population, so the density gap runs the other way from what the area ratio alone would suggest.
Same administrative level, different population systems
Most pairings on this site compare objects of different kinds — a prefecture against a country, an island against an administration. Seoul Special City and Taipei City are both cities, so the outline, the area and the label describe the same kind of object on both sides. That is rarer here than it sounds.
What still differs is how each side counts people. Seoul uses a register-based census; Taipei uses household registration at year-end 2025, which records where a person is registered rather than where they sleep. Taiwanese who have lived abroad for years but kept their Taipei registration are inside this number, and people working in Taipei while registered elsewhere are outside it.
Neither city ends where the city ends
Seoul Special City excludes Incheon and Gyeonggi Province, and Taipei City excludes New Taipei City. In both cases the surrounding region carries several times the core city’s population and supplies a large share of its weekday workforce. A comparison of the two cores is a fair comparison, but it is not a comparison of the two urban regions.
Both boundaries also contain hill country with very few residents — the ridges around Seoul, and Yangmingshan National Park inside Taipei City. The averages on this page therefore describe whole municipalities, not how any given street feels.
Questions people ask
About this geographic comparison
Which is bigger, Seoul or Taipei City?
Seoul is bigger, with a land area about 2.23× that of Taipei City (605.2 vs 271.8 km²).
How do Seoul and Taipei City differ in area, population and density?
Seoul is 2.23× the size of Taipei City — 605.2 km² vs 271.8 km². Population is 3.83× higher; average density is 1.72× higher. Each side’s scope and reference date are set out under “Boundaries and definitions” on this page.
Which city is more crowded?
Seoul, on these averages: its density is roughly 1.7 times Taipei City’s. Neither average describes any particular district, since both boundaries include hill country.
Does Taipei here include New Taipei City?
No. This is Taipei City alone. Everyday use of “Taipei” often means Taipei City plus New Taipei City, which together cover 2,324.3664 km² — 8.6 times the area on this page.
Sources
- Ministry of Land, Infrastructure and Transport, Republic of Korea: Cadastral statistics, reference date 31 December 2024
- Statistics Korea: 2024 Population and Housing Census (register-based)
- Department of Household Registration, Ministry of the Interior: Land area, households and population density by township and district (year-end 2025, ROC 114)
- Department of Household Registration, Ministry of the Interior: Land area, households and population density by township and district (year-end 2025, ROC 114)
Outline data: