British Indian Ocean Territory is about 6,299 times smaller than Japan.

Japan is approximately 377,915 sq km, while British Indian Ocean Territory is approximately 60 sq km, making British Indian Ocean Territory 0.02% the size of Japan. Meanwhile, the population of Japan is ~123.4 million people (123.4 million fewer people live in British Indian Ocean Territory).
Tip: This to-scale comparison of Japan vs. British Indian Ocean Territory uses the Mercator projection, which distorts the size of regions near the poles.
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