Heard Island and McDonald Islands is about 1.8 times bigger than Cook Islands.

Cook Islands is approximately 236 sq km, while Heard Island and McDonald Islands is approximately 412 sq km, making Heard Island and McDonald Islands 75% larger than Cook Islands.
Tip: This to-scale comparison of Cook Islands vs. Heard Island and McDonald Islands uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: Heard Island and McDonald Islands vs. Cook Islands

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