Lake Michigan is about 1.4 times smaller than Lake Superior.

Lake Superior is approximately 82,350 km² (31,795 sq mi), while Lake Michigan is approximately 57,750 km² (22,297 sq mi), making Lake Michigan 70.13% the size of Lake Superior.
Tip: This to-scale comparison of Lake Superior vs. Lake Michigan uses the Mercator projection, which distorts the size of regions near the poles.
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