Nantucket is about 1.2 times smaller than Staten Island.

Staten Island is approximately 150 km² (58 sq mi), while Nantucket is approximately 124 km² (48 sq mi), making Nantucket 82.62% the size of Staten Island.
Tip: This to-scale comparison of Staten Island vs. Nantucket 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.