State size comparison

compared to

Illinois is about 2.6 times smaller than Montana.

Montana is approximately 376,979 sq km, while Illinois is approximately 143,961 sq km, making Illinois 38.19% the size of Montana. Meanwhile, the population of Montana is ~1.1 million people (11.6 million more people live in Illinois).
Tip: This to-scale comparison of Montana vs. Illinois uses the Mercator projection, which distorts the size of regions near the poles.
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