Mackinac Island is about 2.9 times smaller than O'Hare Airport.

O'Hare Airport is approximately 27 km² (11 sq mi), while Mackinac Island is approximately 9.54 km² (3.68 sq mi), making Mackinac Island 34.85% the size of O'Hare Airport.
Tip: This to-scale comparison of O'Hare Airport vs. Mackinac Island uses the Mercator projection, which distorts the size of regions near the poles.
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