Frankfurt is about 1.2 times smaller than Fort Wayne.

Fort Wayne (map shows its 315 named neighbourhoods; the area covers the whole city) is approximately 289 sq km, while Frankfurt is approximately 248 sq km, making Frankfurt 85.78% the size of Fort Wayne.
Tip: This to-scale comparison of Fort Wayne vs. Frankfurt uses the Mercator projection, which distorts the size of regions near the poles.
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