Split backup
Plain definition. A split backup, which Trezor calls Shamir backup, divides a crypto wallet’s backup into several unique recovery shares, and a set number of them together recovers the wallet.
Technical definition. Shamir backup, also known as SLIP39, creates multiple unique recovery shares, each a sequence of 20 or 33 English words carrying part of the cryptographic secret. It is based on Adi Shamir’s algorithm known as Shamir’s Secret Sharing. Combining a preset threshold of shares recreates the master secret (seed), Trezor’s implementation allows 1 to 16 shares but never a threshold of one share, and shares below the threshold leak no information about the shared secret.
On this site
On this site, Split backup comes up in How do I keep my XRP wallet, keys and recovery phrase safe?.
Source
What is Shamir backup? | Trezor Skip to content Products App Coins Learn & Support Search… Search for anything… (trezor.io), read October 1, 2026.