Guam is about 391 times smaller than Utah.

Utah is approximately 212,751 sq km, while Guam is approximately 544 sq km, making Guam 0.26% the size of Utah. Meanwhile, the population of Utah is ~3.5 million people (3.4 million fewer people live in Guam).
Tip: This to-scale comparison of Utah vs. Guam uses the Mercator projection, which distorts the size of regions near the poles.
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