Los Angeles is about 32 times bigger than Jersey City.

Jersey City (map shows its 11 named neighbourhoods; the area covers the whole city) is approximately 38 sq km, while Los Angeles (including the city proper only) is approximately 1,215 sq km, making Los Angeles 3,080% larger than Jersey City.
Tip: This to-scale comparison of Jersey City vs. Los Angeles uses the Mercator projection, which distorts the size of regions near the poles.
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