Montserrat is about 4 times smaller than Heard Island and McDonald Islands.

Heard Island and McDonald Islands is approximately 412 sq km, while Montserrat is approximately 102 sq km, making Montserrat 24.76% the size of Heard Island and McDonald Islands.
Tip: This to-scale comparison of Heard Island and McDonald Islands vs. Montserrat uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: Montserrat vs. Heard Island and McDonald Islands

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