Guam is about 216 times smaller than Eritrea.

Eritrea is approximately 117,600 sq km, while Guam is approximately 544 sq km, making Guam 0.46% the size of Eritrea. Meanwhile, the population of Eritrea is ~6.2 million people (6.0 million fewer people live in Guam).
Tip: This to-scale comparison of Eritrea vs. Guam uses the Mercator projection, which distorts the size of regions near the poles.
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