Florida is about 1.4 times smaller than South Dakota.

South Dakota is approximately 196,540 sq km, while Florida is approximately 139,670 sq km, making Florida 71.06% the size of South Dakota. Meanwhile, the population of South Dakota is ~814,180 people (18.0 million more people live in Florida).
Tip: This to-scale comparison of South Dakota vs. Florida uses the Mercator projection, which distorts the size of regions near the poles.