Papua New Guinea is about 1.9 times bigger than Guinea.

Guinea is approximately 245,857 sq km, while Papua New Guinea is approximately 462,840 sq km, making Papua New Guinea 88% larger than Guinea. Meanwhile, the population of Guinea is ~13.2 million people (3.6 million fewer people live in Papua New Guinea).
Tip: This to-scale comparison of Guinea vs. Papua New Guinea uses the Mercator projection, which distorts the size of regions near the poles.
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