Kuala Lumpur is about 2.5 times smaller than Seoul.

Seoul is approximately 605 sq km, while Kuala Lumpur is approximately 244 sq km, making Kuala Lumpur 40.26% the size of Seoul.
Tip: This to-scale comparison of Seoul vs. Kuala Lumpur uses the Mercator projection, which distorts the size of regions near the poles.
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