Heard Island and McDonald Islands is about 3 times bigger than Christmas Island.

Christmas Island is approximately 135 sq km, while Heard Island and McDonald Islands is approximately 412 sq km, making Heard Island and McDonald Islands 205% larger than Christmas Island.
Tip: This to-scale comparison of Christmas Island vs. Heard Island and McDonald Islands uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: Heard Island and McDonald Islands vs. Christmas Island

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