Mexico City is about 1.4 times smaller than Santiago.

Santiago (area of the 32 comunas of Santiago Province) is approximately 2,030 sq km, while Mexico City is approximately 1,485 sq km, making Mexico City 73.14% the size of Santiago.
Tip: This to-scale comparison of Santiago vs. Mexico City uses the Mercator projection, which distorts the size of regions near the poles.
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