Jacksonville is about 9 times bigger than Boise.

Boise is approximately 221 sq km, while Jacksonville (map shows its 197 named neighbourhoods; the area covers the whole city) is approximately 1,935 sq km, making Jacksonville 778% larger than Boise.
Tip: This to-scale comparison of Boise vs. Jacksonville uses the Mercator projection, which distorts the size of regions near the poles.
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