Kansas City is about 1.5 times smaller than Los Angeles.

Los Angeles (including the city proper only) is approximately 1,215 sq km, while Kansas City (map shows its 145 named neighbourhoods; the area covers the whole city) is approximately 815 sq km, making Kansas City 67.06% the size of Los Angeles.
Tip: This to-scale comparison of Los Angeles vs. Kansas City uses the Mercator projection, which distorts the size of regions near the poles.
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