San Francisco is about 1.4 times bigger than Bellevue.

Bellevue is approximately 87 sq km, while San Francisco (including the city proper only) is approximately 121 sq km, making San Francisco 40% larger than Bellevue.
Tip: This to-scale comparison of Bellevue vs. San Francisco uses the Mercator projection, which distorts the size of regions near the poles.
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