Wisconsin is about 37 times bigger than Sydney.

Sydney (the 30 councils of metropolitan Sydney, without the Blue Mountains, Hawkesbury, Wollondilly and the Central Coast) is approximately 3,810 sq km, while Wisconsin is approximately 140,663 sq km, making Wisconsin 3,592% larger than Sydney.
Tip: This to-scale comparison of Sydney vs. Wisconsin uses the Mercator projection, which distorts the size of regions near the poles.
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