British Indian Ocean Territory is about 5,158 times smaller than Oman.

Oman is approximately 309,500 sq km, while British Indian Ocean Territory is approximately 60 sq km, making British Indian Ocean Territory 0.02% the size of Oman. Meanwhile, the population of Oman is ~5.5 million people (5.5 million fewer people live in British Indian Ocean Territory).
Tip: This to-scale comparison of Oman vs. British Indian Ocean Territory uses the Mercator projection, which distorts the size of regions near the poles.
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