Los Angeles is about 1.2 times smaller than Kauai.

Kauai is approximately 1,435 km² (554 sq mi), while Los Angeles (including the city proper only) is approximately 1,215 sq km, making Los Angeles 84.65% the size of Kauai.
Tip: This to-scale comparison of Kauai vs. Los Angeles uses the Mercator projection, which distorts the size of regions near the poles.
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