Vermont is about 3.3 times smaller than Maine.

Maine is approximately 79,931 sq km, while Vermont is approximately 23,956 sq km, making Vermont 29.97% the size of Maine. Meanwhile, the population of Maine is ~1.3 million people (702,620 fewer people live in Vermont).
Tip: This to-scale comparison of Maine vs. Vermont uses the Mercator projection, which distorts the size of regions near the poles.