Oakland is about 4.8 times smaller than Sao Tome and Principe.

Sao Tome and Principe is approximately 964 sq km, while Oakland is approximately 202 sq km, making Oakland 20.95% the size of Sao Tome and Principe.
Tip: This to-scale comparison of Sao Tome and Principe vs. Oakland uses the Mercator projection, which distorts the size of regions near the poles.