Nauru is about 11 times smaller than Cook Islands.

Cook Islands is approximately 236 sq km, while Nauru is approximately 21 sq km, making Nauru 8.9% the size of Cook Islands. Meanwhile, the population of Cook Islands is ~8,128 people (1,683 more people live in Nauru).
Tip: This to-scale comparison of Cook Islands vs. Nauru uses the Mercator projection, which distorts the size of regions near the poles.
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