Melbourne is about 4.2 times smaller than Beijing.

Beijing is approximately 16,411 sq km, while Melbourne (the 27 councils of metropolitan Melbourne, without the Yarra Ranges, Cardinia, Mornington Peninsula and Nillumbik) is approximately 3,915 sq km, making Melbourne 23.86% the size of Beijing.
Tip: This to-scale comparison of Beijing vs. Melbourne uses the Mercator projection, which distorts the size of regions near the poles.
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