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

Heard Island and McDonald Islands is approximately 412 sq km, while Sao Tome and Principe is approximately 964 sq km, making Sao Tome and Principe 134% larger than Heard Island and McDonald Islands.
Tip: This to-scale comparison of Heard Island and McDonald Islands vs. Sao Tome and Principe uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: Sao Tome and Principe vs. Heard Island and McDonald Islands

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