Peru is about 4.2 times bigger than Oman.

Oman is approximately 309,500 sq km, while Peru is approximately 1,285,216 sq km, making Peru 315% larger than Oman. Meanwhile, the population of Oman is ~5.5 million people (29.1 million more people live in Peru).
Tip: This to-scale comparison of Oman vs. Peru uses the Mercator projection, which distorts the size of regions near the poles.
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