Nearly a tie: Indonesia and Sudan differ by barely 1% in area: about 1,904,569 km² against 1,878,000 km².
Indonesia sits in Asia, Sudan in Africa. On the old Mercator map the latitude gap distorted how large each felt beside the other; at true size the answer is simply 1.01×.
The old Mercator map treated both about equally (1.00× vs 1.1× inflation), so at least their relative sizes were preserved, even if both were drawn at the wrong absolute scale.
Sudan fits 1× into Indonesia.
Indonesia vs Sudan: key figures
| Measure | Indonesia | Sudan |
|---|
| True area | 1,904,569 km² · #15 | 1,878,000 km² · #16 |
| Mercator inflation | 1.00× | 1.1× |
| Apparent on Mercator | 1,907,616 km² | 2,031,808 km² |