Phoenix is about 4.6 times bigger than Jackson.

Jackson (map shows its 125 named neighbourhoods; the area covers the whole city) is approximately 289 sq km, while Phoenix is approximately 1,342 sq km, making Phoenix 364% larger than Jackson.
Tip: This to-scale comparison of Jackson vs. Phoenix 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.