Edinburgh is about 15 times smaller than Sydney.

Sydney (the 30 councils of metropolitan Sydney, without the Blue Mountains, Hawkesbury, Wollondilly and the Central Coast) is approximately 3,810 sq km, while Edinburgh (map shows its 30 named neighbourhoods; the area covers the whole city) is approximately 259 sq km, making Edinburgh 6.8% the size of Sydney.
Tip: This to-scale comparison of Sydney vs. Edinburgh uses the Mercator projection, which distorts the size of regions near the poles.
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