Heard Island and McDonald Islands is about 29 times bigger than Cocos (Keeling) Islands.

Cocos (Keeling) Islands is approximately 14 sq km, while Heard Island and McDonald Islands is approximately 412 sq km, making Heard Island and McDonald Islands 2,843% larger than Cocos (Keeling) Islands.
Tip: This to-scale comparison of Cocos (Keeling) 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. Cocos (Keeling) Islands

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