British Indian Ocean Territory is about 188 times smaller than Gambia.

Gambia is approximately 11,300 sq km, while British Indian Ocean Territory is approximately 60 sq km, making British Indian Ocean Territory 0.53% the size of Gambia. Meanwhile, the population of Gambia is ~2.8 million people (2.8 million fewer people live in British Indian Ocean Territory).
Tip: This to-scale comparison of Gambia vs. British Indian Ocean Territory uses the Mercator projection, which distorts the size of regions near the poles.
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