Montserrat is about 4.9 times bigger than Nauru.

Nauru is approximately 21 sq km, while Montserrat is approximately 102 sq km, making Montserrat 386% larger than Nauru. Meanwhile, the population of Nauru is ~9,811 people (4,397 fewer people live in Montserrat).
Tip: This to-scale comparison of Nauru vs. Montserrat uses the Mercator projection, which distorts the size of regions near the poles.
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