Heard Island and McDonald Islands is about 14 times smaller than Brunei.

Brunei is approximately 5,765 sq km, while Heard Island and McDonald Islands is approximately 412 sq km, making Heard Island and McDonald Islands 7.15% the size of Brunei.
Tip: This to-scale comparison of Brunei 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. Brunei

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