Cook Islands is about 11 times bigger than Nauru.

Nauru is approximately 21 sq km, while Cook Islands is approximately 236 sq km, making Cook Islands 1,024% larger than Nauru. Meanwhile, the population of Nauru is ~9,811 people (1,683 fewer people live in Cook Islands).
Tip: This to-scale comparison of Nauru vs. Cook Islands uses the Mercator projection, which distorts the size of regions near the poles.
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