Catalina Island is about 1.6 times bigger than Nantucket.

Nantucket is approximately 124 km² (48 sq mi), while Catalina Island is approximately 194 km² (75 sq mi), making Catalina Island 57% larger than Nantucket.
Tip: This to-scale comparison of Nantucket vs. Catalina Island uses the Mercator projection, which distorts the size of regions near the poles.
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