Iowa is about 4 times bigger than Guinea-Bissau.

Guinea-Bissau is approximately 36,125 sq km, while Iowa is approximately 144,701 sq km, making Iowa 301% larger than Guinea-Bissau. Meanwhile, the population of Guinea-Bissau is ~2.0 million people (1.0 million more people live in Iowa).
Tip: This to-scale comparison of Guinea-Bissau vs. Iowa uses the Mercator projection, which distorts the size of regions near the poles.