South Georgia and South Sandwich Islands is about 4.7 times smaller than Fiji.

Fiji is approximately 18,274 sq km, while South Georgia and South Sandwich Islands is approximately 3,903 sq km, making South Georgia and South Sandwich Islands 21.36% the size of Fiji.
Tip: This to-scale comparison of Fiji 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. Fiji