California is about 106 times bigger 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 California is approximately 403,882 sq km, making California 10,501% larger than Sydney.
Tip: This to-scale comparison of Sydney vs. California uses the Mercator projection, which distorts the size of regions near the poles.
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