Lake Okeechobee is about 3.7 times bigger than Flathead Lake.

Flathead Lake is approximately 510 km² (197 sq mi), while Lake Okeechobee is approximately 1,890 km² (730 sq mi), making Lake Okeechobee 271% larger than Flathead Lake.
Tip: This to-scale comparison of Flathead Lake vs. Lake Okeechobee uses the Mercator projection, which distorts the size of regions near the poles.
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