Illinois is about 13 times smaller than Indonesia.

Indonesia is approximately 1,904,569 sq km, while Illinois is approximately 143,961 sq km, making Illinois 7.56% the size of Indonesia. Meanwhile, the population of Indonesia is ~277.3 million people (264.5 million fewer people live in Illinois).
Tip: This to-scale comparison of Indonesia vs. Illinois uses the Mercator projection, which distorts the size of regions near the poles.
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