Winterthur is about 18 times smaller than Los Angeles.

Los Angeles (including the city proper only) is approximately 1,215 sq km, while Winterthur is approximately 68 sq km, making Winterthur 5.6% the size of Los Angeles.
Tip: This to-scale comparison of Los Angeles vs. Winterthur uses the Mercator projection, which distorts the size of regions near the poles.
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