Sydney is about 106 times smaller than California.

California is approximately 403,882 sq km, while Sydney (the 30 councils of metropolitan Sydney, without the Blue Mountains, Hawkesbury, Wollondilly and the Central Coast) is approximately 3,810 sq km, making Sydney 0.94% the size of California.
Tip: This to-scale comparison of California vs. Sydney uses the Mercator projection, which distorts the size of regions near the poles.
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