Mac-Storage-Tooltip-256GBAir
Storage
This MacBook Air comes with 256GB of SSD storage.¹ You can configure it with up to 2TB of storage, giving you more space to store your documents, photos, music and apps, as well as extensive video libraries and large data files.
Note: MacBook Air storage is not user accessible. If you think you may need more storage capacity in the future, consider upgrading at the time of purchase.
1.1GB = 1 billion bytes and 1TB = 1 trillion bytes; actual formatted capacity less.