Australia is about 18,789 times bigger than Heard Island and McDonald Islands.

Heard Island and McDonald Islands is approximately 412 sq km, while Australia is approximately 7,741,220 sq km, making Australia 1,878,837% larger than Heard Island and McDonald Islands.
Tip: This to-scale comparison of Heard Island and McDonald Islands vs. Australia uses the Mercator projection, which distorts the size of regions near the poles.

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