Shanghai is about 1.6 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 Shanghai is approximately 6,341 sq km, making Shanghai 62% larger than Melbourne.
Tip: This to-scale comparison of Melbourne vs. Shanghai uses the Mercator projection, which distorts the size of regions near the poles.
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