New Jersey is about 13 times smaller than Michigan.

Michigan is approximately 250,493 sq km, while New Jersey is approximately 19,211 sq km, making New Jersey 7.67% the size of Michigan. Meanwhile, the population of Michigan is ~10.1 million people (579,669 fewer people live in New Jersey).
Tip: This to-scale comparison of Michigan vs. New Jersey uses the Mercator projection, which distorts the size of regions near the poles.
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