Irvine is about 3.6 times smaller than Madrid.

Madrid is approximately 604 sq km, while Irvine (map shows its 24 named neighbourhoods; the area covers the whole city) is approximately 170 sq km, making Irvine 28.12% the size of Madrid.
Tip: This to-scale comparison of Madrid vs. Irvine uses the Mercator projection, which distorts the size of regions near the poles.
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