Bellevue is about 1.4 times smaller than San Francisco.

San Francisco (including the city proper only) is approximately 121 sq km, while Bellevue is approximately 87 sq km, making Bellevue 71.64% the size of San Francisco.
Tip: This to-scale comparison of San Francisco vs. Bellevue uses the Mercator projection, which distorts the size of regions near the poles.
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