Portland is about 5 times smaller than Salt Lake City.

Salt Lake City is approximately 287 sq km, while Portland (map shows its 17 named neighbourhoods; the area covers the whole city) is approximately 56 sq km, making Portland 19.42% the size of Salt Lake City.
Tip: This to-scale comparison of Salt Lake City vs. Portland uses the Mercator projection, which distorts the size of regions near the poles.
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