Costa Rica is about 9 times smaller than Papua New Guinea.

Papua New Guinea is approximately 462,840 sq km, while Costa Rica is approximately 51,100 sq km, making Costa Rica 11.04% the size of Papua New Guinea. Meanwhile, the population of Papua New Guinea is ~10.8 million people (5.6 million fewer people live in Costa Rica).
Tip: This to-scale comparison of Papua New Guinea vs. Costa Rica uses the Mercator projection, which distorts the size of regions near the poles.
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