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

Heard Island and McDonald Islands is approximately 412 sq km, while Cocos (Keeling) Islands is approximately 14 sq km, making Cocos (Keeling) Islands 3.4% the size of Heard Island and McDonald Islands.
Tip: This to-scale comparison of Heard Island and McDonald Islands vs. Cocos (Keeling) Islands uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: Cocos (Keeling) Islands vs. Heard Island and McDonald Islands

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