Mexico City is about 4.6 times smaller than Ho Chi Minh City.

Ho Chi Minh City is approximately 6,773 sq km, while Mexico City is approximately 1,485 sq km, making Mexico City 21.93% the size of Ho Chi Minh City.
Tip: This to-scale comparison of Ho Chi Minh City vs. Mexico City uses the Mercator projection, which distorts the size of regions near the poles.
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