Charlotte is about 3.7 times bigger than Boise.

Boise is approximately 221 sq km, while Charlotte (map shows its 157 named neighbourhoods; the area covers the whole city) is approximately 807 sq km, making Charlotte 266% larger than Boise.
Tip: This to-scale comparison of Boise vs. Charlotte uses the Mercator projection, which distorts the size of regions near the poles.
Our free app, MapSize by MyLifeElsewhere — compare any two places, to scale on your mobile device.