Catalina Island is about 3.6 times bigger than Manhattan.

Manhattan is approximately 55 km² (21 sq mi), while Catalina Island is approximately 194 km² (75 sq mi), making Catalina Island 256% larger than Manhattan.
Tip: This to-scale comparison of Manhattan vs. Catalina Island 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.