New York City is about 9 times smaller than Ho Chi Minh City.

Ho Chi Minh City is approximately 6,773 sq km, while New York City (including all five boroughs: Manhattan, Brooklyn, Queens, The Bronx, and Staten Island) is approximately 781 sq km, making New York City 11.53% the size of Ho Chi Minh City.
Tip: This to-scale comparison of Ho Chi Minh City vs. New York City uses the Mercator projection, which distorts the size of regions near the poles.
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