Lake of the Ozarks is about 2.4 times smaller than Flathead Lake.

Flathead Lake is approximately 510 km² (197 sq mi), while Lake of the Ozarks is approximately 212 km² (82 sq mi), making Lake of the Ozarks 41.51% the size of Flathead Lake.
Tip: This to-scale comparison of Flathead Lake vs. Lake of the Ozarks uses the Mercator projection, which distorts the size of regions near the poles.
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