Heard Island and McDonald Islands is about 5 times smaller than Comoros.

Comoros is approximately 2,235 sq km, while Heard Island and McDonald Islands is approximately 412 sq km, making Heard Island and McDonald Islands 18.43% the size of Comoros.
Tip: This to-scale comparison of Comoros 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. Comoros

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