Ledger Nano S

The Ledger Nano S works as a hardware wallet by keeping a user's private keys inside a physically isolated chip that never touches an internet connection. Transactions are prepared on a computer or phone but must be verified and confirmed on the device's own tiny screen using its two side buttons, so malware on the host machine cannot silently approve a transfer.

Launched by the French company Ledger SAS in 2016, the Nano S paired its USB stick form factor with a CC EAL5+ certified Secure Element chip, the same class of chip used in bank cards and passports. Its original ST31H320 chip offered only 320 KB of combined firmware and app storage, so owners could typically install just three to ten apps at once, though far more coins could be managed over time by swapping apps through the Ledger Live companion software.

Access is protected by a user-chosen PIN, with the device wiping itself after three failed attempts, and recovery relies entirely on a 24-word seed phrase generated during setup, which Ledger itself never sees or stores. No breach of the Secure Element has been publicly documented, though a 2020 leak of Ledger's e-commerce customer database exposed buyer contact details, not any wallet keys.

Ledger phased out the Nano S as its limited memory became a bottleneck, steering buyers toward the USB-C Nano S Plus and other newer models, while rival Trezor devices remain the main alternative in the same entry-level hardware wallet category.