South Korea is about 551 times bigger than Marshall Islands.

Marshall Islands is approximately 181 sq km, while South Korea is approximately 99,720 sq km, making South Korea 54,994% larger than Marshall Islands. Meanwhile, the population of Marshall Islands is ~36,282 people (51.6 million more people live in South Korea).
Tip: This to-scale comparison of Marshall Islands vs. South Korea uses the Mercator projection, which distorts the size of regions near the poles.
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