Ho Chi Minh City is about 1.7 times bigger than Melbourne.

Melbourne (the 27 councils of metropolitan Melbourne, without the Yarra Ranges, Cardinia, Mornington Peninsula and Nillumbik) is approximately 3,915 sq km, while Ho Chi Minh City is approximately 6,773 sq km, making Ho Chi Minh City 73% larger than Melbourne.
Tip: This to-scale comparison of Melbourne vs. Ho Chi Minh City uses the Mercator projection, which distorts the size of regions near the poles.
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