Idaho is about 2.1 times bigger than South Korea.

South Korea is approximately 99,720 sq km, while Idaho is approximately 214,314 sq km, making Idaho 115% larger than South Korea. Meanwhile, the population of South Korea is ~51.8 million people (50.3 million fewer people live in Idaho).
Tip: This to-scale comparison of South Korea vs. Idaho uses the Mercator projection, which distorts the size of regions near the poles.
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