State size comparison

compared to

Illinois is about 1.2 times smaller than Missouri.

Missouri is approximately 178,414 sq km, while Illinois is approximately 143,961 sq km, making Illinois 80.69% the size of Missouri. Meanwhile, the population of Missouri is ~6.0 million people (6.8 million more people live in Illinois).
Tip: This to-scale comparison of Missouri vs. Illinois uses the Mercator projection, which distorts the size of regions near the poles.
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Compare further: Illinois vs. Missouri
Flip Comparison · See true size
See Illinois on top of Missouri
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Cost of Living Comparison · 7 categories - 2026 data
Missouri is 8.7% cheaper than Illinois
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