Sydney is about 38 times smaller than Iowa.

Iowa is approximately 144,701 sq km, while Sydney (the 30 councils of metropolitan Sydney, without the Blue Mountains, Hawkesbury, Wollondilly and the Central Coast) is approximately 3,810 sq km, making Sydney 2.63% the size of Iowa.
Tip: This to-scale comparison of Iowa vs. Sydney uses the Mercator projection, which distorts the size of regions near the poles.
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