Amsterdam is about 4.3 times bigger than Jersey City.

Jersey City (map shows its 11 named neighbourhoods; the area covers the whole city) is approximately 38 sq km, while Amsterdam is approximately 166 sq km, making Amsterdam 334% larger than Jersey City.
Tip: This to-scale comparison of Jersey City vs. Amsterdam 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.