Samoa is about 3.8 times bigger than Tonga.

Tonga is approximately 747 sq km, while Samoa is approximately 2,831 sq km, making Samoa 279% larger than Tonga. Meanwhile, the population of Tonga is ~103,742 people (115,564 more people live in Samoa).
Tip: This to-scale comparison of Tonga vs. Samoa uses the Mercator projection, which distorts the size of regions near the poles.
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