Sydney is about 21 times bigger than San Jose.

San Jose is approximately 180 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 2,017% larger than San Jose.
Tip: This to-scale comparison of San Jose vs. Sydney uses the Mercator projection, which distorts the size of regions near the poles.
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