South Georgia and South Sandwich Islands is about 138 times bigger than Macau.

Macau is approximately 28 sq km, while South Georgia and South Sandwich Islands is approximately 3,903 sq km, making South Georgia and South Sandwich Islands 13,740% larger than Macau.
Tip: This to-scale comparison of Macau 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. Macau