South Korea is about 2 times smaller than Nebraska.

Nebraska is approximately 199,099 sq km, while South Korea is approximately 99,720 sq km, making South Korea 50.09% the size of Nebraska. Meanwhile, the population of Nebraska is ~1.8 million people (50.0 million more people live in South Korea).
Tip: This to-scale comparison of Nebraska vs. South Korea uses the Mercator projection, which distorts the size of regions near the poles.
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