Yellowstone National Park is about 1.4 times smaller than Connecticut.

Connecticut is approximately 12,548 sq km, while Yellowstone National Park is approximately 8,983 km² (3,469 sq mi), making Yellowstone National Park 71.59% the size of Connecticut.
Tip: This to-scale comparison of Connecticut vs. Yellowstone National Park uses the Mercator projection, which distorts the size of regions near the poles.
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