British Indian Ocean Territory is about 129,020 times smaller than Australia.

Australia is approximately 7,741,220 sq km, while British Indian Ocean Territory is approximately 60 sq km, making British Indian Ocean Territory 0.0% the size of Australia. Meanwhile, the population of Australia is ~27.6 million people (27.6 million fewer people live in British Indian Ocean Territory).
Tip: This to-scale comparison of Australia 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. Australia

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