Key West is about 13 times smaller than Milan.

Milan is approximately 182 sq km, while Key West (area of Key West island) is approximately 14 sq km, making Key West 7.48% the size of Milan.
Tip: This to-scale comparison of Milan vs. Key West uses the Mercator projection, which distorts the size of regions near the poles.
Our free app, MapSize by MyLifeElsewhere — compare any two places, to scale on your mobile device.