Estimates for a worldwide collection (USA, EUR, JPN) typically land between 1.7 TB and 1.83 TB .
The total size of a complete Nintendo 3DS ROM set is approximately . This library includes over 1,300 unique retail titles along with digital-only eShop releases and DLC. Core ROM Set Sizes 3ds Complete Rom Set Size
Depending on how the set is curated (regions, duplicates, and file types), the total storage requirements vary: Estimates for a worldwide collection (USA, EUR, JPN)