Place comparison

South Korea compared with California: area, population and density

California has about 4 times South Korea’s land, but South Korea has about 1.3 times California’s population, so it is about 5.3 times as dense.

Place A Grouped by country or region Place B Grouped by country or region

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: South Korea and California. Change the selector above and the page follows, so the reading always matches the tool.

Direct answer

How different are South Korea and California?

South Korea covers 100,459.9 km² (38,788 sq mi); South Korea's area is about 24.9% of California's. Its reported population is 51,805,547; South Korea's population is 1.32 times California's. By average density, South Korea's population density is 5.29 times California's.

Area difference

South Korea's area is about 24.9% of California's 100,459.9 km² (38,788 sq mi) · 403,676.6 km² (155,860 sq mi)

Population difference

South Korea's population is 1.32 times California's 51,805,547 · 39,355,309

Density difference

South Korea's population density is 5.29 times California's 515.7 /km² (1,336 /sq mi) · 97.5 /km² (253 /sq mi)

Full data and sources for each place: South Korea area & population, California area & population

Straight-line distance between geometric centres: about 9276 km; time difference: 17 hours (16 hours during daylight saving time).

On a familiar scale

South Korea ≈ the size of Virginia (reference rung) 1,939 m² of land per resident
California ≈ 60% of Texas 10,257 m² of land per resident

Reference scales come from U.S. Census Bureau: 2025 Gazetteer Files: land area of states and counties , as of 2025-01-01.

How to read it

Four South Koreas of land fit in California, and South Korea still has 12 million more people.

Geography and shape

Both are long, mountainous and coastal, and both concentrate their people in a few metropolitan areas: South Korea around Seoul and Busan, California around Los Angeles, the San Francisco Bay Area and San Diego. California is simply much larger, running about 1,240 km from north to south.

Population context

South Korea has 51,805,547 people on 100,460 km², about 516 per km². California has an estimated 39,355,309 on 403,677 km² of land, about 97 per km². South Korea has about 1.3 times California’s population on about a quarter of its land.

Boundaries and definitions

South Korea uses its register-based census for 1 November 2024 and registered cadastral land. California uses the Census Bureau’s Vintage 2025 estimate for 1 July 2025 and the state’s land area, which excludes 20,289 km² of water. Including that water, California is about 4.2 South Koreas instead of 4.0.

South Korea: Register-based census population, including Korean and foreign residents; registered cadastral land area.

California: The State of California: 403,676.56 km² of land and 39,355,309 residents. Area is the Census Bureau’s land area (ALAND) for the state in the 2025 Gazetteer, which excludes inland and coastal water — another 20,289 km², so the land-plus-water total is 423,965 km². Population is the Census Bureau’s Vintage 2025 resident estimate for 1 July 2025, not a census count. The outline is Natural Earth’s admin-1 polygon for California, including the Channel Islands, and measures about 1.5% larger than the official land area because its coastline encloses bays such as San Francisco Bay. California uses Pacific Time (UTC−8, UTC−7 in summer).

In-depth guide

How should South Korea and California be understood in context?

California is the most populous US state, and South Korea still has about 12 million more people — on about a quarter of California’s land.

A quarter of the land, a third more people

California’s 403,677 km² of land is about 4 times South Korea’s 100,460 km². South Korea’s 51.8 million people are about 1.3 times California’s 39.4 million, so it averages about 516 people per km² against California’s 97 — about 5.3 times as dense.

Both places leave most of their mountains lightly settled and put their people in a few coastal and lowland metropolitan areas, so the gap between their densest neighbourhoods is much smaller than the gap between their averages.

Questions people ask

About this geographic comparison

Which is bigger, South Korea or California?

California is bigger, with a land area about 4.02× that of South Korea (South Korea 100,459.9 vs California 403,676.6 km², or 38,788 sq mi vs 155,860 sq mi).

How big is South Korea compared to California?

California has 403,676.6 km² (155,860 sq mi) and South Korea has 100,459.9 km² (38,788 sq mi): the ratio is 4.02×. Conversely, South Korea has 24.9% of California's area.

Does South Korea or California have more people?

South Korea has 51,805,547 people (2024-11-01), versus 39,355,309 in California (2025-07-01): 1.32×. In reverse, California has 76% of South Korea's population. South Korea is 24.9% the size of California — 100,459.9 km² vs 403,676.6 km² (38,788 sq mi vs 155,860 sq mi). Population is 1.32× higher; average density is 5.29× higher. Each side’s scope and reference date are set out under “Boundaries and definitions” on this page.

Is South Korea bigger than California?

No. California is bigger, with a land area about 4.02× that of South Korea (South Korea 100,459.9 vs California 403,676.6 km², or 38,788 sq mi vs 155,860 sq mi). The area difference is 303,216.7 km². California has 403,676.6 km² (155,860 sq mi) and South Korea has 100,459.9 km² (38,788 sq mi): the ratio is 4.02×. Conversely, South Korea has 24.9% of California's area. No. California’s 403,677 km² of land is about 4 times South Korea’s 100,460 km². South Korea does have more people: about 51.8 million against 39.4 million.

How many times does South Korea fit into California?

By land area, South Korea fits into California about 4.02 times (403,676.6 km² vs 100,459.9 km², or 155,860 sq mi vs 38,788 sq mi). It is an area ratio, not a jigsaw fit: coastlines and shapes differ, which the outlines on this page show at one scale.

How much more crowded is South Korea than California?

About 5.3 times on average: 516 people per km² against 97. Both averages include large mountain areas with few residents.

Sources

Outline data:

Natural Earth · Public domain