South Georgia and South Sandwich Islands is about 5 times bigger than Dominica.

Dominica is approximately 751 sq km, while South Georgia and South Sandwich Islands is approximately 3,903 sq km, making South Georgia and South Sandwich Islands 420% larger than Dominica.
Tip: This to-scale comparison of Dominica vs. South Georgia and South Sandwich Islands uses the Mercator projection, which distorts the size of regions near the poles.
Compare further: South Georgia and South Sandwich Islands vs. Dominica