British Indian Ocean Territory is about 7 times smaller than Heard Island and McDonald Islands.

Heard Island and McDonald Islands is approximately 412 sq km, while British Indian Ocean Territory is approximately 60 sq km, making British Indian Ocean Territory 14.56% the size of Heard Island and McDonald Islands.
Tip: This to-scale comparison of Heard Island and McDonald Islands vs. British Indian Ocean Territory uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: British Indian Ocean Territory vs. Heard Island and McDonald Islands

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