Seattle is about 1.3 times smaller than Jackson.

Jackson (map shows its 125 named neighbourhoods; the area covers the whole city) is approximately 289 sq km, while Seattle is approximately 217 sq km, making Seattle 75.12% the size of Jackson.
Tip: This to-scale comparison of Jackson vs. Seattle 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.