Melbourne is about 3.2 times bigger than Los Angeles.

Los Angeles (including the city proper only) is approximately 1,215 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 222% larger than Los Angeles.
Tip: This to-scale comparison of Los Angeles vs. Melbourne uses the Mercator projection, which distorts the size of regions near the poles.
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