British Indian Ocean Territory is about 13 times smaller than Bahrain.

Bahrain is approximately 760 sq km, while British Indian Ocean Territory is approximately 60 sq km, making British Indian Ocean Territory 7.89% the size of Bahrain. Meanwhile, the population of Bahrain is ~1.6 million people (1.6 million fewer people live in British Indian Ocean Territory).
Tip: This to-scale comparison of Bahrain vs. British Indian Ocean Territory uses the Mercator projection, which distorts the size of regions near the poles.
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