British Indian Ocean Territory is about 3.9 times smaller than Cook Islands.

Cook Islands is approximately 236 sq km, while British Indian Ocean Territory is approximately 60 sq km, making British Indian Ocean Territory 25.42% the size of Cook Islands. Meanwhile, the population of Cook Islands is ~14,222 people (11,222 fewer people live in British Indian Ocean Territory).
Tip: This to-scale comparison of Cook Islands vs. British Indian Ocean Territory uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: British Indian Ocean Territory vs. Cook Islands

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