Heard Island and McDonald Islands is about 433 times smaller than Missouri.

Missouri is approximately 178,414 sq km, while Heard Island and McDonald Islands is approximately 412 sq km, making Heard Island and McDonald Islands 0.23% the size of Missouri.
Tip: This to-scale comparison of Missouri vs. Heard Island and McDonald Islands uses the Mercator projection, which distorts the size of regions near the poles.

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