Heard Island and McDonald Islands is about 2.3 times smaller than Sao Tome and Principe.

Sao Tome and Principe is approximately 964 sq km, while Heard Island and McDonald Islands is approximately 412 sq km, making Heard Island and McDonald Islands 42.74% the size of Sao Tome and Principe.
Tip: This to-scale comparison of Sao Tome and Principe vs. Heard Island and McDonald Islands uses the Mercator projection, which distorts the size of regions near the poles.

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