Newark is about 31 times smaller than Jacksonville.

Jacksonville (map shows its 197 named neighbourhoods; the area covers the whole city) is approximately 1,935 sq km, while Newark (map shows its 20 named neighbourhoods; the area covers the whole city) is approximately 63 sq km, making Newark 3.23% the size of Jacksonville.
Tip: This to-scale comparison of Jacksonville vs. Newark uses the Mercator projection, which distorts the size of regions near the poles.
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