Japan is about 1.5 times bigger than Wyoming.

Wyoming is approximately 251,489 sq km, while Japan is approximately 377,915 sq km, making Japan 50% larger than Wyoming. Meanwhile, the population of Wyoming is ~563,626 people (123.7 million more people live in Japan).
Tip: This to-scale comparison of Wyoming vs. Japan uses the Mercator projection, which distorts the size of regions near the poles.
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