Nauru is about 2,433 times smaller than Costa Rica.

Costa Rica is approximately 51,100 sq km, while Nauru is approximately 21 sq km, making Nauru 0.04% the size of Costa Rica. Meanwhile, the population of Costa Rica is ~5.2 million people (5.2 million fewer people live in Nauru).
Tip: This to-scale comparison of Costa Rica vs. Nauru uses the Mercator projection, which distorts the size of regions near the poles.
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