Lake Okeechobee is about 1.3 times bigger than Kauai.

Kauai is approximately 1,435 km² (554 sq mi), while Lake Okeechobee is approximately 1,890 km² (730 sq mi), making Lake Okeechobee 32% larger than Kauai.
Tip: This to-scale comparison of Kauai vs. Lake Okeechobee uses the Mercator projection, which distorts the size of regions near the poles.
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