Kauai is about 2.1 times smaller than Yosemite National Park.

Yosemite National Park is approximately 3,027 km² (1,169 sq mi), while Kauai is approximately 1,435 km² (554 sq mi), making Kauai 47.4% the size of Yosemite National Park.
Tip: This to-scale comparison of Yosemite National Park vs. Kauai uses the Mercator projection, which distorts the size of regions near the poles.
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