Sao Tome and Principe is about 20 times bigger than Bouvet Island.

Bouvet Island is approximately 49 sq km, while Sao Tome and Principe is approximately 964 sq km, making Sao Tome and Principe 1,867% larger than Bouvet Island.
Tip: This to-scale comparison of Bouvet Island vs. Sao Tome and Principe uses the Mercator projection, which distorts the size of regions near the poles.