State size comparison

compared to

Oklahoma is about 1.2 times bigger than Illinois.

Illinois is approximately 143,961 sq km, while Oklahoma is approximately 177,847 sq km, making Oklahoma 24% larger than Illinois. Meanwhile, the population of Illinois is ~12.8 million people (9.1 million fewer people live in Oklahoma).
Tip: This to-scale comparison of Illinois vs. Oklahoma uses the Mercator projection, which distorts the size of regions near the poles.
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Compare further: Oklahoma vs. Illinois

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See Oklahoma on top of Illinois
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Make 38.6% more money in Illinois
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Illinois is 7.7% more expensive than Oklahoma
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