Long Island is about 2.9 times smaller than Big Island of Hawaii.

Big Island of Hawaii is approximately 10,434 km² (4,029 sq mi), while Long Island is approximately 3,566 km² (1,377 sq mi), making Long Island 34.18% the size of Big Island of Hawaii.
Tip: This to-scale comparison of Big Island of Hawaii vs. Long Island uses the Mercator projection, which distorts the size of regions near the poles.
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