Sierra Leone is about 3.5 times bigger than Massachusetts.

Massachusetts is approximately 20,306 sq km, while Sierra Leone is approximately 71,740 sq km, making Sierra Leone 253% larger than Massachusetts. Meanwhile, the population of Massachusetts is ~6.5 million people (2.1 million more people live in Sierra Leone).
Tip: This to-scale comparison of Massachusetts vs. Sierra Leone uses the Mercator projection, which distorts the size of regions near the poles.